lisp/vc-rcs.el

   1 ;;; vc-rcs.el --- support for RCS version-control
   2
   3 ;; Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
   4 ;;   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
   5
   6 ;; Author:     FSF (see vc.el for full credits)
   7 ;; Maintainer: Andre Spiegel <spiegel@gnu.org>
   8
   9 ;; $Id$
  10
  11 ;; This file is part of GNU Emacs.
  12
  13 ;; GNU Emacs is free software: you can redistribute it and/or modify
  14 ;; it under the terms of the GNU General Public License as published by
  15 ;; the Free Software Foundation, either version 3 of the License, or
  16 ;; (at your option) any later version.
  17
  18 ;; GNU Emacs is distributed in the hope that it will be useful,
  19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 ;; GNU General Public License for more details.
  22
  23 ;; You should have received a copy of the GNU General Public License
  24 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  25
  26 ;;; Commentary:
  27
  28 ;; See vc.el
  29
  30 ;;; Code:
  31
  32 ;;;
  33 ;;; Customization options
  34 ;;;
  35
  36 (eval-when-compile
  37   (require 'cl)
  38   (require 'vc))
  39
  40 (defcustom vc-rcs-release nil
  41   "*The release number of your RCS installation, as a string.
  42 If nil, VC itself computes this value when it is first needed."
  43   :type '(choice (const :tag "Auto" nil)
  44                  (string :tag "Specified")
  45                  (const :tag "Unknown" unknown))
  46   :group 'vc)
  47
  48 (defcustom vc-rcs-register-switches nil
  49   "*Extra switches for registering a file in RCS.
  50 A string or list of strings.  These are passed to the checkin program
  51 by \\[vc-rcs-register]."
  52   :type '(choice (const :tag "None" nil)
  53                  (string :tag "Argument String")
  54                  (repeat :tag "Argument List"
  55                          :value ("")
  56                          string))
  57   :version "21.1"
  58   :group 'vc)
  59
  60 (defcustom vc-rcs-diff-switches nil
  61   "*A string or list of strings specifying extra switches for rcsdiff under VC."
  62   :type '(choice (const :tag "None" nil)
  63                  (string :tag "Argument String")
  64                  (repeat :tag "Argument List"
  65                          :value ("")
  66                          string))
  67   :version "21.1"
  68   :group 'vc)
  69
  70 (defcustom vc-rcs-header (or (cdr (assoc 'RCS vc-header-alist)) '("\$Id\$"))
  71   "*Header keywords to be inserted by `vc-insert-headers'."
  72   :type '(repeat string)
  73   :version "21.1"
  74   :group 'vc)
  75
  76 (defcustom vc-rcsdiff-knows-brief nil
  77   "*Indicates whether rcsdiff understands the --brief option.
  78 The value is either `yes', `no', or nil.  If it is nil, VC tries
  79 to use --brief and sets this variable to remember whether it worked."
  80   :type '(choice (const :tag "Work out" nil) (const yes) (const no))
  81   :group 'vc)
  82
  83 ;;;###autoload
  84 (defcustom vc-rcs-master-templates
  85   '("%sRCS/%s,v" "%s%s,v" "%sRCS/%s")
  86   "*Where to look for RCS master files.
  87 For a description of possible values, see `vc-check-master-templates'."
  88   :type '(choice (const :tag "Use standard RCS file names"
  89                         '("%sRCS/%s,v" "%s%s,v" "%sRCS/%s"))
  90                  (repeat :tag "User-specified"
  91                          (choice string
  92                                  function)))
  93   :version "21.1"
  94   :group 'vc)
  95
  96 \f
  97 ;;; Properties of the backend
  98
  99 (defun vc-rcs-revision-granularity () 'file)
 100
 101 (defun vc-rcs-checkout-model (files)
 102   "RCS-specific version of `vc-checkout-model'."
 103   (let ((file (if (consp files) (car files) files))
 104         result)
 105     (when vc-consult-headers
 106       (vc-file-setprop file 'vc-checkout-model nil)
 107       (vc-rcs-consult-headers file)
 108       (setq result (vc-file-getprop file 'vc-checkout-model)))
 109     (or result
 110         (progn (vc-rcs-fetch-master-state file)
 111                (vc-file-getprop file 'vc-checkout-model)))))
 112
 113 ;;;
 114 ;;; State-querying functions
 115 ;;;
 116
 117 ;; The autoload cookie below places vc-rcs-registered directly into
 118 ;; loaddefs.el, so that vc-rcs.el does not need to be loaded for
 119 ;; every file that is visited.
 120 ;;;###autoload
 121 (progn
 122 (defun vc-rcs-registered (f) (vc-default-registered 'RCS f)))
 123
 124 (defun vc-rcs-state (file)
 125   "Implementation of `vc-state' for RCS."
 126   (if (not (vc-rcs-registered file))
 127       'unregistered
 128     (or (boundp 'vc-rcs-headers-result)
 129         (and vc-consult-headers
 130              (vc-rcs-consult-headers file)))
 131     (let ((state
 132            ;; vc-working-revision might not be known; in that case the
 133            ;; property is nil.  vc-rcs-fetch-master-state knows how to
 134            ;; handle that.
 135            (vc-rcs-fetch-master-state file
 136                                       (vc-file-getprop file
 137                                                        'vc-working-revision))))
 138       (if (not (eq state 'up-to-date))
 139           state
 140         (if (vc-workfile-unchanged-p file)
 141             'up-to-date
 142           (if (eq (vc-rcs-checkout-model (list file)) 'locking)
 143               'unlocked-changes
 144             'edited))))))
 145
 146 (defun vc-rcs-state-heuristic (file)
 147   "State heuristic for RCS."
 148   (let (vc-rcs-headers-result)
 149     (if (and vc-consult-headers
 150              (setq vc-rcs-headers-result
 151                    (vc-rcs-consult-headers file))
 152              (eq vc-rcs-headers-result 'rev-and-lock))
 153         (let ((state (vc-file-getprop file 'vc-state)))
 154           ;; If the headers say that the file is not locked, the
 155           ;; permissions can tell us whether locking is used for
 156           ;; the file or not.
 157           (if (and (eq state 'up-to-date)
 158                    (not (vc-mistrust-permissions file)))
 159               (cond
 160                ((string-match ".rw..-..-." (nth 8 (file-attributes file)))
 161                 (vc-file-setprop file 'vc-checkout-model 'implicit)
 162                 (setq state
 163                       (if (vc-rcs-workfile-is-newer file)
 164                           'edited
 165                         'up-to-date)))
 166                ((string-match ".r-..-..-." (nth 8 (file-attributes file)))
 167                 (vc-file-setprop file 'vc-checkout-model 'locking))))
 168           state)
 169       (if (not (vc-mistrust-permissions file))
 170           (let* ((attributes  (file-attributes file 'string))
 171                  (owner-name  (nth 2 attributes))
 172                  (permissions (nth 8 attributes)))
 173             (cond ((string-match ".r-..-..-." permissions)
 174                    (vc-file-setprop file 'vc-checkout-model 'locking)
 175                    'up-to-date)
 176                   ((string-match ".rw..-..-." permissions)
 177                    (if (eq (vc-rcs-checkout-model file) 'locking)
 178                        (if (file-ownership-preserved-p file)
 179                            'edited
 180                          owner-name)
 181                      (if (vc-rcs-workfile-is-newer file)
 182                          'edited
 183                        'up-to-date)))
 184                   (t
 185                    ;; Strange permissions.  Fall through to
 186                    ;; expensive state computation.
 187                    (vc-rcs-state file))))
 188         (vc-rcs-state file)))))
 189
 190 (defun vc-rcs-dir-status (dir update-function)
 191   ;; FIXME: this function should be rewritten or `vc-expand-dirs'
 192   ;; should be changed to take a backend parameter.  Using
 193   ;; `vc-expand-dirs' is not TRTD because it returns files from
 194   ;; multiple backends.  It should also return 'unregistered files.
 195
 196   ;; Doing individual vc-state calls is painful but there
 197   ;; is no better way in RCS-land.
 198   (let ((flist (vc-expand-dirs (list dir)))
 199         (result nil))
 200     (dolist (file flist)
 201       (let ((state (vc-state file))
 202             (frel (file-relative-name file)))
 203         (when (and (eq (vc-backend file) 'RCS)
 204                    (not (eq state 'up-to-date)))
 205           (push (list frel state) result))))
 206     (funcall update-function result)))
 207
 208 (defun vc-rcs-working-revision (file)
 209   "RCS-specific version of `vc-working-revision'."
 210   (or (and vc-consult-headers
 211            (vc-rcs-consult-headers file)
 212            (vc-file-getprop file 'vc-working-revision))
 213       (progn
 214         (vc-rcs-fetch-master-state file)
 215         (vc-file-getprop file 'vc-working-revision))))
 216
 217 (defun vc-rcs-latest-on-branch-p (file &optional version)
 218   "Return non-nil if workfile version of FILE is the latest on its branch.
 219 When VERSION is given, perform check for that version."
 220   (unless version (setq version (vc-working-revision file)))
 221   (with-temp-buffer
 222     (string= version
 223              (if (vc-trunk-p version)
 224                  (progn
 225                    ;; Compare VERSION to the head version number.
 226                    (vc-insert-file (vc-name file) "^[0-9]")
 227                    (vc-parse-buffer "^head[ \t\n]+\\([^;]+\\);" 1))
 228                ;; If we are not on the trunk, we need to examine the
 229                ;; whole current branch.
 230                (vc-insert-file (vc-name file) "^desc")
 231                (vc-rcs-find-most-recent-rev (vc-branch-part version))))))
 232
 233 (defun vc-rcs-workfile-unchanged-p (file)
 234   "RCS-specific implementation of `vc-workfile-unchanged-p'."
 235   ;; Try to use rcsdiff --brief.  If rcsdiff does not understand that,
 236   ;; do a double take and remember the fact for the future
 237   (let* ((version (concat "-r" (vc-working-revision file)))
 238          (status (if (eq vc-rcsdiff-knows-brief 'no)
 239                      (vc-do-command "*vc*" 1 "rcsdiff" file version)
 240                    (vc-do-command "*vc*" 2 "rcsdiff" file "--brief" version))))
 241     (if (eq status 2)
 242         (if (not vc-rcsdiff-knows-brief)
 243             (setq vc-rcsdiff-knows-brief 'no
 244                   status (vc-do-command "*vc*" 1 "rcsdiff" file version))
 245           (error "rcsdiff failed"))
 246       (if (not vc-rcsdiff-knows-brief) (setq vc-rcsdiff-knows-brief 'yes)))
 247     ;; The workfile is unchanged if rcsdiff found no differences.
 248     (zerop status)))
 249
 250 (defun vc-rcs-find-file-not-found-hook ()
 251   (if (yes-or-no-p
 252        (format "File %s was lost; check out from version control? "
 253                (file-name-nondirectory buffer-file-name)))
 254       (save-excursion
 255         (require 'vc)
 256         (let ((default-directory (file-name-directory buffer-file-name)))
 257           (not (vc-error-occurred (vc-checkout buffer-file-name)))))))
 258 \f
 259 ;;;
 260 ;;; State-changing functions
 261 ;;;
 262
 263 (defun vc-rcs-create-repo ()
 264   "Create a new RCS repository."
 265   ;; RCS is totally file-oriented, so all we have to do is make the directory
 266   (make-directory "RCS"))
 267
 268 (defun vc-rcs-register (files &optional rev comment)
 269   "Register FILES into the RCS version-control system.
 270 REV is the optional revision number for the files.  COMMENT can be used
 271 to provide an initial description for each FILES.
 272
 273 `vc-register-switches' and `vc-rcs-register-switches' are passed to
 274 the RCS command (in that order).
 275
 276 Automatically retrieve a read-only version of the file with keywords
 277 expanded if `vc-keep-workfiles' is non-nil, otherwise, delete the workfile."
 278   (let (subdir name)
 279     (dolist (file files)
 280       (and (not (file-exists-p
 281                  (setq subdir (expand-file-name "RCS"
 282                                                 (file-name-directory file)))))
 283            (not (directory-files (file-name-directory file)
 284                                  nil ".*,v$" t))
 285            (yes-or-no-p "Create RCS subdirectory? ")
 286            (make-directory subdir))
 287       (apply 'vc-do-command "*vc*" 0 "ci" file
 288              ;; if available, use the secure registering option
 289              (and (vc-rcs-release-p "5.6.4") "-i")
 290              (concat (if vc-keep-workfiles "-u" "-r") rev)
 291              (and comment (concat "-t-" comment))
 292              (vc-switches 'RCS 'register))
 293       ;; parse output to find master file name and workfile version
 294       (with-current-buffer "*vc*"
 295         (goto-char (point-min))
 296         (if (not (setq name
 297                        (if (looking-at (concat "^\\(.*\\)  <--  "
 298                                                (file-name-nondirectory file)))
 299                            (match-string 1))))
 300             ;; if we couldn't find the master name,
 301             ;; run vc-rcs-registered to get it
 302             ;; (will be stored into the vc-name property)
 303             (vc-rcs-registered file)
 304           (vc-file-setprop file 'vc-name
 305                            (if (file-name-absolute-p name)
 306                                name
 307                              (expand-file-name
 308                               name
 309                               (file-name-directory file))))))
 310       (vc-file-setprop file 'vc-working-revision
 311                        (if (re-search-forward
 312                             "^initial revision: \\([0-9.]+\\).*\n"
 313                             nil t)
 314                            (match-string 1))))))
 315
 316 (defun vc-rcs-responsible-p (file)
 317   "Return non-nil if RCS thinks it would be responsible for registering FILE."
 318   ;; TODO: check for all the patterns in vc-rcs-master-templates
 319   (file-directory-p (expand-file-name "RCS" (file-name-directory file))))
 320
 321 (defun vc-rcs-receive-file (file rev)
 322   "Implementation of receive-file for RCS."
 323   (let ((checkout-model (vc-rcs-checkout-model (list file))))
 324     (vc-rcs-register file rev "")
 325     (when (eq checkout-model 'implicit)
 326       (vc-rcs-set-non-strict-locking file))
 327     (vc-rcs-set-default-branch file (concat rev ".1"))))
 328
 329 (defun vc-rcs-unregister (file)
 330   "Unregister FILE from RCS.
 331 If this leaves the RCS subdirectory empty, ask the user
 332 whether to remove it."
 333   (let* ((master (vc-name file))
 334          (dir (file-name-directory master))
 335          (backup-info (find-backup-file-name master)))
 336     (if (not backup-info)
 337         (delete-file master)
 338       (rename-file master (car backup-info) 'ok-if-already-exists)
 339       (dolist (f (cdr backup-info)) (ignore-errors (delete-file f))))
 340     (and (string= (file-name-nondirectory (directory-file-name dir)) "RCS")
 341          ;; check whether RCS dir is empty, i.e. it does not
 342          ;; contain any files except "." and ".."
 343          (not (directory-files dir nil
 344                                "^\\([^.]\\|\\.[^.]\\|\\.\\.[^.]\\).*"))
 345          (yes-or-no-p (format "Directory %s is empty; remove it? " dir))
 346          (delete-directory dir))))
 347
 348 (defun vc-rcs-checkin (files rev comment)
 349   "RCS-specific version of `vc-backend-checkin'."
 350   (let ((switches (vc-switches 'RCS 'checkin)))
 351     ;; Now operate on the files
 352     (dolist (file (vc-expand-dirs files))
 353       (let ((old-version (vc-working-revision file)) new-version
 354             (default-branch (vc-file-getprop file 'vc-rcs-default-branch)))
 355         ;; Force branch creation if an appropriate
 356         ;; default branch has been set.
 357         (and (not rev)
 358              default-branch
 359              (string-match (concat "^" (regexp-quote old-version) "\\.")
 360                            default-branch)
 361              (setq rev default-branch)
 362              (setq switches (cons "-f" switches)))
 363         (if (and (not rev) old-version)
 364             (setq rev (vc-branch-part old-version)))
 365         (apply 'vc-do-command "*vc*" 0 "ci" (vc-name file)
 366                ;; if available, use the secure check-in option
 367                (and (vc-rcs-release-p "5.6.4") "-j")
 368                (concat (if vc-keep-workfiles "-u" "-r") rev)
 369                (concat "-m" comment)
 370                switches)
 371         (vc-file-setprop file 'vc-working-revision nil)
 372
 373         ;; determine the new workfile version
 374         (set-buffer "*vc*")
 375         (goto-char (point-min))
 376         (when (or (re-search-forward
 377                    "new revision: \\([0-9.]+\\);" nil t)
 378                   (re-search-forward
 379                    "reverting to previous revision \\([0-9.]+\\)" nil t))
 380           (setq new-version (match-string 1))
 381           (vc-file-setprop file 'vc-working-revision new-version))
 382
 383         ;; if we got to a different branch, adjust the default
 384         ;; branch accordingly
 385         (cond
 386          ((and old-version new-version
 387                (not (string= (vc-branch-part old-version)
 388                              (vc-branch-part new-version))))
 389           (vc-rcs-set-default-branch file
 390                                      (if (vc-trunk-p new-version) nil
 391                                        (vc-branch-part new-version)))
 392           ;; If this is an old RCS release, we might have
 393           ;; to remove a remaining lock.
 394           (if (not (vc-rcs-release-p "5.6.2"))
 395               ;; exit status of 1 is also accepted.
 396               ;; It means that the lock was removed before.
 397               (vc-do-command "*vc*" 1 "rcs" (vc-name file)
 398                              (concat "-u" old-version)))))))))
 399
 400 (defun vc-rcs-find-revision (file rev buffer)
 401   (apply 'vc-do-command
 402          (or buffer "*vc*") 0 "co" (vc-name file)
 403          "-q" ;; suppress diagnostic output
 404          (concat "-p" rev)
 405          (vc-switches 'RCS 'checkout)))
 406
 407 (defun vc-rcs-checkout (file &optional editable rev)
 408   "Retrieve a copy of a saved version of FILE. If FILE is a directory,
 409 attempt the checkout for all registered files beneath it."
 410   (if (file-directory-p file)
 411       (mapc 'vc-rcs-checkout (vc-expand-dirs (list file)))
 412     (let ((file-buffer (get-file-buffer file))
 413           switches)
 414       (message "Checking out %s..." file)
 415       (save-excursion
 416         ;; Change buffers to get local value of vc-checkout-switches.
 417         (if file-buffer (set-buffer file-buffer))
 418         (setq switches (vc-switches 'RCS 'checkout))
 419         ;; Save this buffer's default-directory
 420         ;; and use save-excursion to make sure it is restored
 421         ;; in the same buffer it was saved in.
 422         (let ((default-directory default-directory))
 423           (save-excursion
 424             ;; Adjust the default-directory so that the check-out creates
 425             ;; the file in the right place.
 426             (setq default-directory (file-name-directory file))
 427             (let (new-version)
 428               ;; if we should go to the head of the trunk,
 429               ;; clear the default branch first
 430               (and rev (string= rev "")
 431                    (vc-rcs-set-default-branch file nil))
 432               ;; now do the checkout
 433               (apply 'vc-do-command
 434                      "*vc*" 0 "co" (vc-name file)
 435                      ;; If locking is not strict, force to overwrite
 436                      ;; the writable workfile.
 437                      (if (eq (vc-rcs-checkout-model (list file)) 'implicit) "-f")
 438                      (if editable "-l")
 439                      (if (stringp rev)
 440                          ;; a literal revision was specified
 441                          (concat "-r" rev)
 442                        (let ((workrev (vc-working-revision file)))
 443                          (if workrev
 444                              (concat "-r"
 445                                      (if (not rev)
 446                                          ;; no revision specified:
 447                                          ;; use current workfile version
 448                                          workrev
 449                                        ;; REV is t ...
 450                                        (if (not (vc-trunk-p workrev))
 451                                            ;; ... go to head of current branch
 452                                            (vc-branch-part workrev)
 453                                          ;; ... go to head of trunk
 454                                          (vc-rcs-set-default-branch file
 455                                                                   nil)
 456                                        ""))))))
 457                    switches)
 458             ;; determine the new workfile version
 459             (with-current-buffer "*vc*"
 460               (setq new-version
 461                     (vc-parse-buffer "^revision \\([0-9.]+\\).*\n" 1)))
 462             (vc-file-setprop file 'vc-working-revision new-version)
 463             ;; if necessary, adjust the default branch
 464             (and rev (not (string= rev ""))
 465                  (vc-rcs-set-default-branch
 466                   file
 467                   (if (vc-rcs-latest-on-branch-p file new-version)
 468                       (if (vc-trunk-p new-version) nil
 469                         (vc-branch-part new-version))
 470                     new-version)))))
 471         (message "Checking out %s...done" file))))))
 472
 473 (defun vc-rcs-rollback (files)
 474   "Roll back, undoing the most recent checkins of FILES.  Directories are
 475 expanded to all regidtered subfuiles in them."
 476   (if (not files)
 477       (error "RCS backend doesn't support directory-level rollback."))
 478   (dolist (file (vc-expand-dirs files))
 479           (let* ((discard (vc-working-revision file))
 480                  (previous (if (vc-trunk-p discard) "" (vc-branch-part discard)))
 481                  (config (current-window-configuration))
 482                  (done nil))
 483             (if (null (yes-or-no-p (format "Remove version %s from %s history? "
 484                                            discard file)))
 485                 (error "Aborted"))
 486             (message "Removing revision %s from %s." discard file)
 487             (vc-do-command "*vc*" 0 "rcs" (vc-name file) (concat "-o" discard))
 488             ;; Check out the most recent remaining version.  If it
 489             ;; fails, because the whole branch got deleted, do a
 490             ;; double-take and check out the version where the branch
 491             ;; started.
 492             (while (not done)
 493               (condition-case err
 494                   (progn
 495                     (vc-do-command "*vc*" 0 "co" (vc-name file) "-f"
 496                                    (concat "-u" previous))
 497                     (setq done t))
 498                 (error (set-buffer "*vc*")
 499                        (goto-char (point-min))
 500                        (if (search-forward "no side branches present for" nil t)
 501                            (progn (setq previous (vc-branch-part previous))
 502                                   (vc-rcs-set-default-branch file previous)
 503                                   ;; vc-do-command popped up a window with
 504                                   ;; the error message.  Get rid of it, by
 505                                   ;; restoring the old window configuration.
 506                                   (set-window-configuration config))
 507                          ;; No, it was some other error: re-signal it.
 508                          (signal (car err) (cdr err)))))))))
 509
 510 (defun vc-rcs-revert (file &optional contents-done)
 511   "Revert FILE to the version it was based on.  If FILE is a directory,
 512 revert all registered files beneath it."
 513   (if (file-directory-p file)
 514       (mapc 'vc-rcs-revert (vc-expand-dirs (list file)))
 515     (vc-do-command "*vc*" 0 "co" (vc-name file) "-f"
 516                    (concat (if (eq (vc-state file) 'edited) "-u" "-r")
 517                            (vc-working-revision file)))))
 518
 519 (defun vc-rcs-merge (file first-version &optional second-version)
 520   "Merge changes into current working copy of FILE.
 521 The changes are between FIRST-VERSION and SECOND-VERSION."
 522   (vc-do-command "*vc*" 1 "rcsmerge" (vc-name file)
 523                  "-kk"                  ; ignore keyword conflicts
 524                  (concat "-r" first-version)
 525                  (if second-version (concat "-r" second-version))))
 526
 527 (defun vc-rcs-steal-lock (file &optional rev)
 528   "Steal the lock on the current workfile for FILE and revision REV.
 529 If FUILEis a directory, steal the lock on all registered files beneath it.
 530 Needs RCS 5.6.2 or later for -M."
 531   (if (file-directory-p file)
 532       (mapc 'vc-rcs-steal-lock (vc-expand-dirs (list file)))
 533     (vc-do-command "*vc*" 0 "rcs" (vc-name file) "-M" (concat "-u" rev))
 534     ;; Do a real checkout after stealing the lock, so that we see
 535     ;; expanded headers.
 536     (vc-do-command "*vc*" 0 "co" (vc-name file) "-f" (concat "-l" rev))))
 537
 538 (defun vc-rcs-modify-change-comment (files rev comment)
 539   "Modify the change comments change on FILES on a specified REV.  If FILE is a
 540 directory the operation is applied to all registered files beneath it."
 541   (dolist (file (vc-expand-dirs files))
 542     (vc-do-command "*vc*" 0 "rcs" (vc-name file)
 543                    (concat "-m" rev ":" comment))))
 544
 545 \f
 546 ;;;
 547 ;;; History functions
 548 ;;;
 549
 550 (defun vc-rcs-print-log (files &optional buffer)
 551   "Get change log associated with FILE.  If FILE is a
 552 directory the operation is applied to all registered files beneath it."
 553   (vc-do-command (or buffer "*vc*") 0 "rlog" (mapcar 'vc-name (vc-expand-dirs files))))
 554
 555 (defun vc-rcs-diff (files &optional oldvers newvers buffer)
 556   "Get a difference report using RCS between two sets of files."
 557   (apply 'vc-do-command (or buffer "*vc-diff*")
 558          1              ;; Always go synchronous, the repo is local
 559          "rcsdiff" (vc-expand-dirs files)
 560          (append (list "-q"
 561                        (and oldvers (concat "-r" oldvers))
 562                        (and newvers (concat "-r" newvers)))
 563                  (vc-switches 'RCS 'diff))))
 564
 565 (defun vc-rcs-comment-history (file)
 566   "Return a string with all log entries stored in BACKEND for FILE."
 567   (with-current-buffer "*vc*"
 568     ;; Has to be written this way, this function is used by the CVS backend too
 569     (vc-call-backend (vc-backend file) 'print-log (list file))
 570     ;; Remove cruft
 571     (let ((separator (concat "^-+\nrevision [0-9.]+\ndate: .*\n"
 572                              "\\(branches: .*;\n\\)?"
 573                              "\\(\\*\\*\\* empty log message \\*\\*\\*\n\\)?")))
 574       (goto-char (point-max)) (forward-line -1)
 575       (while (looking-at "=*\n")
 576         (delete-char (- (match-end 0) (match-beginning 0)))
 577         (forward-line -1))
 578       (goto-char (point-min))
 579       (if (looking-at "[\b\t\n\v\f\r ]+")
 580           (delete-char (- (match-end 0) (match-beginning 0))))
 581       (goto-char (point-min))
 582       (re-search-forward separator nil t)
 583       (delete-region (point-min) (point))
 584       (while (re-search-forward separator nil t)
 585         (delete-region (match-beginning 0) (match-end 0))))
 586     ;; Return the de-crufted comment list
 587     (buffer-string)))
 588
 589 (defun vc-rcs-annotate-command (file buffer &optional revision)
 590   "Annotate FILE, inserting the results in BUFFER.
 591 Optional arg REVISION is a revision to annotate from."
 592   (vc-setup-buffer buffer)
 593   ;; Aside from the "head revision on the trunk", the instructions for
 594   ;; each revision on the trunk are an ordered list of kill and insert
 595   ;; commands necessary to go from the chronologically-following
 596   ;; revision to this one.  That is, associated with revision N are
 597   ;; edits that applied to revision N+1 would result in revision N.
 598   ;;
 599   ;; On a branch, however, (some) things are inverted: the commands
 600   ;; listed are those necessary to go from the chronologically-preceding
 601   ;; revision to this one.  That is, associated with revision N are
 602   ;; edits that applied to revision N-1 would result in revision N.
 603   ;;
 604   ;; So, to get per-line history info, we apply reverse-chronological
 605   ;; edits, starting with the head revision on the trunk, all the way
 606   ;; back through the initial revision (typically "1.1" or similar),
 607   ;; then apply forward-chronological edits -- keeping track of which
 608   ;; revision is associated with each inserted line -- until we reach
 609   ;; the desired revision for display (which may be either on the trunk
 610   ;; or on a branch).
 611   (let* ((tree (with-temp-buffer
 612                  (insert-file-contents (vc-rcs-registered file))
 613                  (vc-rcs-parse)))
 614          (revisions (cdr (assq 'revisions tree)))
 615          ;; The revision N whose instructions we currently are processing.
 616          (cur (cdr (assq 'head (cdr (assq 'headers tree)))))
 617          ;; Alist from the parse tree for N.
 618          (meta (cdr (assoc cur revisions)))
 619          ;; Point and temporary string, respectively.
 620          p s
 621          ;; "Next-branch list".  Nil means the desired revision to
 622          ;; display lives on the trunk.  Non-nil means it lives on a
 623          ;; branch, in which case the value is a list of revision pairs
 624          ;; (PARENT . CHILD), the first PARENT being on the trunk, that
 625          ;; links each series of revisions in the path from the initial
 626          ;; revision to the desired revision to display.
 627          nbls
 628          ;; "Path-accumulate-predicate plus revision/date/author".
 629          ;; Until set, forward-chronological edits are not accumulated.
 630          ;; Once set, its value (updated every revision) is used for
 631          ;; the text property `:vc-rcs-r/d/a' for inserts during
 632          ;; processing of forward-chronological instructions for N.
 633          ;; See internal func `r/d/a'.
 634          prda
 635          ;; List of forward-chronological instructions, each of the
 636          ;; form: (POS . ACTION), where POS is a buffer position.  If
 637          ;; ACTION is a string, it is inserted, otherwise it is taken as
 638          ;; the number of characters to be deleted.
 639          path
 640          ;; N+1.  When `cur' is "", this is the initial revision.
 641          pre)
 642     (unless revision
 643       (setq revision cur))
 644     (unless (assoc revision revisions)
 645       (error "No such revision: %s" revision))
 646     ;; Find which branches (if any) must be included in the edits.
 647     (let ((par revision)
 648           bpt kids)
 649       (while (setq bpt (vc-branch-part par)
 650                    par (vc-branch-part bpt))
 651         (setq kids (cdr (assq 'branches (cdr (assoc par revisions)))))
 652         ;; A branchpoint may have multiple children.  Find the right one.
 653         (while (not (string= bpt (vc-branch-part (car kids))))
 654           (setq kids (cdr kids)))
 655         (push (cons par (car kids)) nbls)))
 656     ;; Start with the full text.
 657     (set-buffer buffer)
 658     (insert (cdr (assq 'text meta)))
 659     ;; Apply reverse-chronological edits on the trunk, computing and
 660     ;; accumulating forward-chronological edits after some point, for
 661     ;; later.
 662     (flet ((r/d/a () (vector pre
 663                              (cdr (assq 'date meta))
 664                              (cdr (assq 'author meta)))))
 665       (while (when (setq pre cur cur (cdr (assq 'next meta)))
 666                (not (string= "" cur)))
 667         (setq
 668          ;; Start accumulating the forward-chronological edits when N+1
 669          ;; on the trunk is either the desired revision to display, or
 670          ;; the appropriate branchpoint for it.  Do this before
 671          ;; updating `meta' since `r/d/a' uses N+1's `meta' value.
 672          prda (when (or prda (string= (if nbls (caar nbls) revision) pre))
 673                 (r/d/a))
 674          meta (cdr (assoc cur revisions)))
 675         ;; Edits in the parse tree specify a line number (in the buffer
 676         ;; *BEFORE* editing occurs) to start from, but line numbers
 677         ;; change as a result of edits.  To DTRT, we apply edits in
 678         ;; order of descending buffer position so that edits further
 679         ;; down in the buffer occur first w/o corrupting specified
 680         ;; buffer positions of edits occurring towards the beginning of
 681         ;; the buffer.  In this way we avoid using markers.  A pleasant
 682         ;; property of this approach is ability to push instructions
 683         ;; onto `path' directly, w/o need to maintain rev boundaries.
 684         (dolist (insn (cdr (assq :insn meta)))
 685           (goto-line (pop insn))
 686           (setq p (point))
 687           (case (pop insn)
 688             (k (setq s (buffer-substring-no-properties
 689                         p (progn (forward-line (car insn))
 690                                  (point))))
 691                (when prda
 692                  (push `(,p . ,(propertize s :vc-rcs-r/d/a prda)) path))
 693                (delete-region p (point)))
 694             (i (setq s (car insn))
 695                (when prda
 696                  (push `(,p . ,(length s)) path))
 697                (insert s)))))
 698       ;; For the initial revision, setting `:vc-rcs-r/d/a' directly is
 699       ;; equivalent to pushing an insert instruction (of the entire buffer
 700       ;; contents) onto `path' then erasing the buffer, but less wasteful.
 701       (put-text-property (point-min) (point-max) :vc-rcs-r/d/a (r/d/a))
 702       ;; Now apply the forward-chronological edits for the trunk.
 703       (dolist (insn path)
 704         (goto-char (pop insn))
 705         (if (stringp insn)
 706             (insert insn)
 707           (delete-char insn)))
 708       ;; Now apply the forward-chronological edits (directly from the
 709       ;; parse-tree) for the branch(es), if necessary.  We re-use vars
 710       ;; `pre' and `meta' for the sake of internal func `r/d/a'.
 711       (while nbls
 712         (setq pre (cdr (pop nbls)))
 713         (while (progn
 714                  (setq meta (cdr (assoc pre revisions))
 715                        prda nil)
 716                  (dolist (insn (cdr (assq :insn meta)))
 717                    (goto-line (pop insn))
 718                    (case (pop insn)
 719                      (k (delete-region
 720                          (point) (progn (forward-line (car insn))
 721                                         (point))))
 722                      (i (insert (propertize
 723                                  (car insn)
 724                                  :vc-rcs-r/d/a
 725                                  (or prda (setq prda (r/d/a))))))))
 726                  (prog1 (not (string= (if nbls (caar nbls) revision) pre))
 727                    (setq pre (cdr (assq 'next meta)))))))))
 728   ;; Lastly, for each line, insert at bol nicely-formatted history info.
 729   ;; We do two passes to collect summary information used to minimize
 730   ;; the annotation's usage of screen real-estate: (1) Consider rendered
 731   ;; width of revision plus author together as a unit; and (2) Omit
 732   ;; author entirely if all authors are the same as the user.
 733   (let ((ht (make-hash-table :test 'eq))
 734         (me (user-login-name))
 735         (maxw 0)
 736         (all-me t)
 737         rda w a)
 738     (goto-char (point-max))
 739     (while (not (bobp))
 740       (forward-line -1)
 741       (setq rda (get-text-property (point) :vc-rcs-r/d/a))
 742       (unless (gethash rda ht)
 743         (setq a (aref rda 2)
 744               all-me (and all-me (string= a me)))
 745         (puthash rda (setq w (+ (length (aref rda 0))
 746                                 (length a)))
 747                  ht)
 748         (setq maxw (max w maxw))))
 749     (let ((padding (make-string maxw 32)))
 750       (flet ((pad (w) (substring-no-properties padding w))
 751              (render (rda &rest ls)
 752                      (propertize
 753                       (apply 'concat
 754                              (format-time-string "%Y-%m-%d" (aref rda 1))
 755                              "  "
 756                              (aref rda 0)
 757                              ls)
 758                       :vc-annotate-prefix t
 759                       :vc-rcs-r/d/a rda)))
 760         (maphash
 761          (if all-me
 762              (lambda (rda w)
 763                (puthash rda (render rda (pad w) ": ") ht))
 764            (lambda (rda w)
 765              (puthash rda (render rda " " (pad w) " " (aref rda 2) ": ") ht)))
 766          ht)))
 767     (while (not (eobp))
 768       (insert (gethash (get-text-property (point) :vc-rcs-r/d/a) ht))
 769       (forward-line 1))))
 770
 771 (defun vc-rcs-annotate-current-time ()
 772   "Return the current time, based at midnight of the current day, and
 773 encoded as fractional days."
 774   (vc-annotate-convert-time
 775    (apply 'encode-time 0 0 0 (nthcdr 3 (decode-time (current-time))))))
 776
 777 (defun vc-rcs-annotate-time ()
 778   "Return the time of the next annotation (as fraction of days)
 779 systime, or nil if there is none.  Also, reposition point."
 780   (unless (eobp)
 781     (prog1 (vc-annotate-convert-time
 782             (aref (get-text-property (point) :vc-rcs-r/d/a) 1))
 783       (goto-char (next-single-property-change (point) :vc-annotate-prefix)))))
 784
 785 (defun vc-rcs-annotate-extract-revision-at-line ()
 786   (aref (get-text-property (point) :vc-rcs-r/d/a) 0))
 787
 788 \f
 789 ;;;
 790 ;;; Tag system
 791 ;;;
 792
 793 (defun vc-rcs-create-tag (backend dir name branchp)
 794   (when branchp
 795     (error "RCS backend %s does not support module branches" backend))
 796   (let ((result (vc-tag-precondition dir)))
 797     (if (stringp result)
 798         (error "File %s is not up-to-date" result)
 799       (vc-file-tree-walk
 800        dir
 801        (lambda (f)
 802          (vc-do-command "*vc*" 0 "rcs" (vc-name f) (concat "-n" name ":")))))))
 803
 804 \f
 805 ;;;
 806 ;;; Miscellaneous
 807 ;;;
 808
 809 (defun vc-rcs-check-headers ()
 810   "Check if the current file has any headers in it."
 811   (save-excursion
 812     (goto-char (point-min))
 813          (re-search-forward "\\$[A-Za-z\300-\326\330-\366\370-\377]+\
 814 \\(: [\t -#%-\176\240-\377]*\\)?\\$" nil t)))
 815
 816 (defun vc-rcs-clear-headers ()
 817   "Implementation of vc-clear-headers for RCS."
 818   (let ((case-fold-search nil))
 819     (goto-char (point-min))
 820     (while (re-search-forward
 821             (concat "\\$\\(Author\\|Date\\|Header\\|Id\\|Locker\\|Name\\|"
 822                     "RCSfile\\|Revision\\|Source\\|State\\): [^$\n]+\\$")
 823             nil t)
 824       (replace-match "$\\1$"))))
 825
 826 (defun vc-rcs-rename-file (old new)
 827   ;; Just move the master file (using vc-rcs-master-templates).
 828   (vc-rename-master (vc-name old) new vc-rcs-master-templates))
 829
 830 \f
 831 ;;;
 832 ;;; Internal functions
 833 ;;;
 834
 835 (defun vc-rcs-root (dir)
 836   (vc-find-root dir "RCS" t))
 837
 838 (defun vc-rcs-workfile-is-newer (file)
 839   "Return non-nil if FILE is newer than its RCS master.
 840 This likely means that FILE has been changed with respect
 841 to its master version."
 842   (let ((file-time (nth 5 (file-attributes file)))
 843         (master-time (nth 5 (file-attributes (vc-name file)))))
 844     (or (> (nth 0 file-time) (nth 0 master-time))
 845         (and (= (nth 0 file-time) (nth 0 master-time))
 846              (> (nth 1 file-time) (nth 1 master-time))))))
 847
 848 (defun vc-rcs-find-most-recent-rev (branch)
 849   "Find most recent revision on BRANCH."
 850   (goto-char (point-min))
 851   (let ((latest-rev -1) value)
 852     (while (re-search-forward (concat "^\\(" (regexp-quote branch)
 853                                       "\\.\\([0-9]+\\)\\)\ndate[ \t]+[0-9.]+;")
 854                               nil t)
 855       (let ((rev (string-to-number (match-string 2))))
 856         (when (< latest-rev rev)
 857           (setq latest-rev rev)
 858           (setq value (match-string 1)))))
 859     (or value
 860         (vc-branch-part branch))))
 861
 862 (defun vc-rcs-fetch-master-state (file &optional working-revision)
 863   "Compute the master file's idea of the state of FILE.
 864 If a WORKFILE-VERSION is given, compute the state of that version,
 865 otherwise determine the workfile version based on the master file.
 866 This function sets the properties `vc-working-revision' and
 867 `vc-checkout-model' to their correct values, based on the master
 868 file."
 869   (with-temp-buffer
 870     (if (or (not (vc-insert-file (vc-name file) "^[0-9]"))
 871             (progn (goto-char (point-min))
 872                    (not (looking-at "^head[ \t\n]+[^;]+;$"))))
 873         (error "File %s is not an RCS master file" (vc-name file)))
 874     (let ((workfile-is-latest nil)
 875           (default-branch (vc-parse-buffer "^branch[ \t\n]+\\([^;]*\\);" 1)))
 876       (vc-file-setprop file 'vc-rcs-default-branch default-branch)
 877       (unless working-revision
 878         ;; Workfile version not known yet.  Determine that first.  It
 879         ;; is either the head of the trunk, the head of the default
 880         ;; branch, or the "default branch" itself, if that is a full
 881         ;; revision number.
 882         (cond
 883          ;; no default branch
 884          ((or (not default-branch) (string= "" default-branch))
 885           (setq working-revision
 886                 (vc-parse-buffer "^head[ \t\n]+\\([^;]+\\);" 1))
 887           (setq workfile-is-latest t))
 888          ;; default branch is actually a revision
 889          ((string-match "^[0-9]+\\.[0-9]+\\(\\.[0-9]+\\.[0-9]+\\)*$"
 890                         default-branch)
 891           (setq working-revision default-branch))
 892          ;; else, search for the head of the default branch
 893          (t (vc-insert-file (vc-name file) "^desc")
 894             (setq working-revision
 895                   (vc-rcs-find-most-recent-rev default-branch))
 896             (setq workfile-is-latest t)))
 897         (vc-file-setprop file 'vc-working-revision working-revision))
 898       ;; Check strict locking
 899       (goto-char (point-min))
 900       (vc-file-setprop file 'vc-checkout-model
 901                        (if (re-search-forward ";[ \t\n]*strict;" nil t)
 902                            'locking 'implicit))
 903       ;; Compute state of workfile version
 904       (goto-char (point-min))
 905       (let ((locking-user
 906              (vc-parse-buffer (concat "^locks[ \t\n]+[^;]*[ \t\n]+\\([^:]+\\):"
 907                                       (regexp-quote working-revision)
 908                                       "[^0-9.]")
 909                               1)))
 910         (cond
 911          ;; not locked
 912          ((not locking-user)
 913           (if (or workfile-is-latest
 914                   (vc-rcs-latest-on-branch-p file working-revision))
 915               ;; workfile version is latest on branch
 916               'up-to-date
 917             ;; workfile version is not latest on branch
 918             'needs-update))
 919          ;; locked by the calling user
 920          ((and (stringp locking-user)
 921                (string= locking-user (vc-user-login-name file)))
 922           ;; Don't call `vc-rcs-checkout-model' to avoid inf-looping.
 923           (if (or (eq (vc-file-getprop file 'vc-checkout-model) 'locking)
 924                   workfile-is-latest
 925                   (vc-rcs-latest-on-branch-p file working-revision))
 926               'edited
 927             ;; Locking is not used for the file, but the owner does
 928             ;; have a lock, and there is a higher version on the current
 929             ;; branch.  Not sure if this can occur, and if it is right
 930             ;; to use `needs-merge' in this case.
 931             'needs-merge))
 932          ;; locked by somebody else
 933          ((stringp locking-user)
 934           locking-user)
 935          (t
 936           (error "Error getting state of RCS file")))))))
 937
 938 (defun vc-rcs-consult-headers (file)
 939   "Search for RCS headers in FILE, and set properties accordingly.
 940
 941 Returns: nil            if no headers were found
 942          'rev           if a workfile revision was found
 943          'rev-and-lock  if revision and lock info was found"
 944   (cond
 945    ((not (get-file-buffer file)) nil)
 946    ((let (status version locking-user)
 947      (save-excursion
 948       (set-buffer (get-file-buffer file))
 949       (goto-char (point-min))
 950       (cond
 951        ;; search for $Id or $Header
 952        ;; -------------------------
 953        ;; The `\ 's below avoid an RCS 5.7 bug when checking in this file.
 954        ((or (and (search-forward "$Id\ : " nil t)
 955                  (looking-at "[^ ]+ \\([0-9.]+\\) "))
 956             (and (progn (goto-char (point-min))
 957                         (search-forward "$Header\ : " nil t))
 958                  (looking-at "[^ ]+ \\([0-9.]+\\) ")))
 959         (goto-char (match-end 0))
 960         ;; if found, store the revision number ...
 961         (setq version (match-string-no-properties 1))
 962         ;; ... and check for the locking state
 963         (cond
 964          ((looking-at
 965            (concat "[0-9]+[/-][01][0-9][/-][0-3][0-9] "             ; date
 966             "[0-2][0-9]:[0-5][0-9]+:[0-6][0-9]+\\([+-][0-9:]+\\)? " ; time
 967                    "[^ ]+ [^ ]+ "))                       ; author & state
 968           (goto-char (match-end 0)) ; [0-6] in regexp handles leap seconds
 969           (cond
 970            ;; unlocked revision
 971            ((looking-at "\\$")
 972             (setq locking-user 'none)
 973             (setq status 'rev-and-lock))
 974            ;; revision is locked by some user
 975            ((looking-at "\\([^ ]+\\) \\$")
 976             (setq locking-user (match-string-no-properties 1))
 977             (setq status 'rev-and-lock))
 978            ;; everything else: false
 979            (nil)))
 980          ;; unexpected information in
 981          ;; keyword string --> quit
 982          (nil)))
 983        ;; search for $Revision
 984        ;; --------------------
 985        ((re-search-forward (concat "\\$"
 986                                    "Revision: \\([0-9.]+\\) \\$")
 987                            nil t)
 988         ;; if found, store the revision number ...
 989         (setq version (match-string-no-properties 1))
 990         ;; and see if there's any lock information
 991         (goto-char (point-min))
 992         (if (re-search-forward (concat "\\$" "Locker:") nil t)
 993             (cond ((looking-at " \\([^ ]+\\) \\$")
 994                    (setq locking-user (match-string-no-properties 1))
 995                    (setq status 'rev-and-lock))
 996                   ((looking-at " *\\$")
 997                    (setq locking-user 'none)
 998                    (setq status 'rev-and-lock))
 999                   (t
1000                    (setq locking-user 'none)
1001                    (setq status 'rev-and-lock)))
1002           (setq status 'rev)))
1003        ;; else: nothing found
1004        ;; -------------------
1005        (t nil)))
1006      (if status (vc-file-setprop file 'vc-working-revision version))
1007      (and (eq status 'rev-and-lock)
1008           (vc-file-setprop file 'vc-state
1009                            (cond
1010                             ((eq locking-user 'none) 'up-to-date)
1011                             ((string= locking-user (vc-user-login-name file))
1012                              'edited)
1013                             (t locking-user)))
1014           ;; If the file has headers, we don't want to query the
1015           ;; master file, because that would eliminate all the
1016           ;; performance gain the headers brought us.  We therefore
1017           ;; use a heuristic now to find out whether locking is used
1018           ;; for this file.  If we trust the file permissions, and the
1019           ;; file is not locked, then if the file is read-only we
1020           ;; assume that locking is used for the file, otherwise
1021           ;; locking is not used.
1022           (not (vc-mistrust-permissions file))
1023           (vc-up-to-date-p file)
1024           (if (string-match ".r-..-..-." (nth 8 (file-attributes file)))
1025               (vc-file-setprop file 'vc-checkout-model 'locking)
1026             (vc-file-setprop file 'vc-checkout-model 'implicit)))
1027      status))))
1028
1029 (defun vc-release-greater-or-equal (r1 r2)
1030   "Compare release numbers, represented as strings.
1031 Release components are assumed cardinal numbers, not decimal fractions
1032 \(5.10 is a higher release than 5.9\).  Omitted fields are considered
1033 lower \(5.6.7 is earlier than 5.6.7.1\).  Comparison runs till the end
1034 of the string is found, or a non-numeric component shows up \(5.6.7 is
1035 earlier than \"5.6.7 beta\", which is probably not what you want in
1036 some cases\).  This code is suitable for existing RCS release numbers.
1037 CVS releases are handled reasonably, too \(1.3 < 1.4* < 1.5\)."
1038   (let (v1 v2 i1 i2)
1039     (catch 'done
1040       (or (and (string-match "^\\.?\\([0-9]+\\)" r1)
1041                (setq i1 (match-end 0))
1042                (setq v1 (string-to-number (match-string 1 r1)))
1043                (or (and (string-match "^\\.?\\([0-9]+\\)" r2)
1044                         (setq i2 (match-end 0))
1045                         (setq v2 (string-to-number (match-string 1 r2)))
1046                         (if (> v1 v2) (throw 'done t)
1047                           (if (< v1 v2) (throw 'done nil)
1048                             (throw 'done
1049                                    (vc-release-greater-or-equal
1050                                     (substring r1 i1)
1051                                     (substring r2 i2)))))))
1052                    (throw 'done t)))
1053           (or (and (string-match "^\\.?\\([0-9]+\\)" r2)
1054                    (throw 'done nil))
1055               (throw 'done t)))))
1056
1057 (defun vc-rcs-release-p (release)
1058   "Return t if we have RELEASE or better."
1059   (let ((installation (vc-rcs-system-release)))
1060     (if (and installation
1061              (not (eq installation 'unknown)))
1062         (vc-release-greater-or-equal installation release))))
1063
1064 (defun vc-rcs-system-release ()
1065   "Return the RCS release installed on this system, as a string.
1066 Return symbol UNKNOWN if the release cannot be deducted.  The user can
1067 override this using variable `vc-rcs-release'.
1068
1069 If the user has not set variable `vc-rcs-release' and it is nil,
1070 variable `vc-rcs-release' is set to the returned value."
1071   (or vc-rcs-release
1072       (setq vc-rcs-release
1073             (or (and (zerop (vc-do-command "*vc*" nil "rcs" nil "-V"))
1074                      (with-current-buffer (get-buffer "*vc*")
1075                        (vc-parse-buffer "^RCS version \\([0-9.]+ *.*\\)" 1)))
1076                 'unknown))))
1077
1078 (defun vc-rcs-set-non-strict-locking (file)
1079   (vc-do-command "*vc*" 0 "rcs" file "-U")
1080   (vc-file-setprop file 'vc-checkout-model 'implicit)
1081   (set-file-modes file (logior (file-modes file) 128)))
1082
1083 (defun vc-rcs-set-default-branch (file branch)
1084   (vc-do-command "*vc*" 0 "rcs" (vc-name file) (concat "-b" branch))
1085   (vc-file-setprop file 'vc-rcs-default-branch branch))
1086
1087 (defun vc-rcs-parse (&optional buffer)
1088   "Parse current buffer, presumed to be in RCS-style masterfile format.
1089 Optional arg BUFFER specifies another buffer to parse.  Return an alist
1090 of two elements, w/ keys `headers' and `revisions' and values in turn
1091 sub-alists.  For `headers', the values unless otherwise specified are
1092 strings and the keys are:
1093
1094   desc     -- description
1095   head     -- latest revision
1096   branch   -- the branch the \"head revision\" lies on;
1097               absent if the head revision lies on the trunk
1098   access   -- ???
1099   symbols  -- sub-alist of (SYMBOL . REVISION) elements
1100   locks    -- if file is checked out, something like \"ttn:1.7\"
1101   strict   -- t if \"strict locking\" is in effect, otherwise nil
1102   comment  -- may be absent; typically something like \"# \" or \"; \"
1103   expand   -- may be absent; ???
1104
1105 For `revisions', the car is REVISION (string), the cdr a sub-alist,
1106 with string values (unless otherwise specified) and keys:
1107
1108   date     -- a time value (like that returned by `encode-time'); as a
1109               special case, a year value less than 100 is augmented by 1900
1110   author   -- username
1111   state    -- typically \"Exp\" or \"Rel\"
1112   branches -- list of revisions that begin branches from this revision
1113   next     -- on the trunk: the chronologically-preceding revision, or \"\";
1114               on a branch: the chronologically-following revision, or \"\"
1115   log      -- change log entry
1116   text     -- for the head revision on the trunk, the body of the file;
1117               other revisions have `:insn' instead
1118   :insn    -- for non-head revisions, a list of parsed instructions
1119               in one of two forms, in both cases START meaning \"first
1120               go to line START\":
1121                - `(START k COUNT)' -- kill COUNT lines
1122                - `(START i TEXT)'  -- insert TEXT (a string)
1123               The list is in descending order by START.
1124
1125 The `:insn' key is a keyword to distinguish it as a vc-rcs.el extension."
1126   (setq buffer (get-buffer (or buffer (current-buffer))))
1127   (set-buffer buffer)
1128   ;; An RCS masterfile can be viewed as containing four regular (for the
1129   ;; most part) sections: (a) the "headers", (b) the "rev headers", (c)
1130   ;; the "description" and (d) the "rev bodies", in that order.  In the
1131   ;; returned alist (see docstring), elements from (b) and (d) are
1132   ;; combined pairwise to form the "revisions", while those from (a) and
1133   ;; (c) are simply combined to form the "headers".
1134   ;;
1135   ;; Loosely speaking, each section contains a series of alternating
1136   ;; "tags" and "printed representations".  In the (b) and (d), many
1137   ;; such series can appear, and a revision number on a line by itself
1138   ;; precedes the series of tags and printed representations associated
1139   ;; with it.
1140   ;;
1141   ;; In (a) and (b), the printed representations (with the exception of
1142   ;; the `comment' tag in the headers) terminate with a semicolon, which
1143   ;; is NOT part of the "value" finally associated with the tag.  All
1144   ;; other printed representations are in "@@-format"; there is an "@",
1145   ;; the middle part (to be translated into the value), another "@" and
1146   ;; a newline.  Each "@@" in the middle part indicates the position of
1147   ;; a single "@" (and consequently the requirement of an additional
1148   ;; initial step when translating to the value).
1149   ;;
1150   ;; Parser state includes vars that collect parts of the return value...
1151   (let ((desc nil) (headers nil) (revs nil)
1152         ;; ... as well as vars that support a single-pass, tag-assisted,
1153         ;; minimal-data-copying scan.  Basically -- skirting around the
1154         ;; grouping by revision required in (b) and (d) -- we repeatedly
1155         ;; and context-sensitively read a tag (that MUST be present),
1156         ;; determine the bounds of the printed representation, translate
1157         ;; it into a value, and push the tag plus value onto one of the
1158         ;; collection vars.  Finally, we return the parse tree
1159         ;; incorporating the values of the collection vars (see "rv").
1160         ;;
1161         ;; A symbol or string to keep track of context (for error messages).
1162         context
1163         ;; A symbol, the current tag.
1164         tok
1165         ;; Region (begin and end buffer positions) of the printed
1166         ;; representation for the current tag.
1167         b e
1168         ;; A list of buffer positions where "@@" can be found within the
1169         ;; printed representation region.  For each location, we push two
1170         ;; elements onto the list, 1+ and 2+ the location, respectively,
1171         ;; with the 2+ appearing at the head.  In this way, the expression
1172         ;;   `(,e ,@@-holes ,b)
1173         ;; describes regions that can be concatenated (in reverse order)
1174         ;; to "de-@@-format" the printed representation as the first step
1175         ;; to translating it into some value.  See internal func `gather'.
1176         @-holes)
1177     (flet ((sw () (skip-chars-forward " \t\n")) ; i.e., `[:space:]'
1178            (at (tag) (save-excursion (eq tag (read buffer))))
1179            (to-eol () (buffer-substring-no-properties
1180                        (point) (progn (forward-line 1)
1181                                       (1- (point)))))
1182            (to-semi () (setq b (point)
1183                              e (progn (search-forward ";")
1184                                       (1- (point)))))
1185            (to-one@ () (setq @-holes nil
1186                              b (progn (search-forward "@") (point))
1187                              e (progn (while (and (search-forward "@")
1188                                                   (= ?@ (char-after))
1189                                                   (progn
1190                                                     (push (point) @-holes)
1191                                                     (forward-char 1)
1192                                                     (push (point) @-holes))))
1193                                       (1- (point)))))
1194            (tok+val (set-b+e name &optional proc)
1195                     (unless (eq name (setq tok (read buffer)))
1196                       (error "Missing `%s' while parsing %s" name context))
1197                     (sw)
1198                     (funcall set-b+e)
1199                     (cons tok (if proc
1200                                   (funcall proc)
1201                                 (buffer-substring-no-properties b e))))
1202            (k-semi (name &optional proc) (tok+val 'to-semi name proc))
1203            (gather () (let ((pairs `(,e ,@@-holes ,b))
1204                             acc)
1205                         (while pairs
1206                           (push (buffer-substring-no-properties
1207                                  (cadr pairs) (car pairs))
1208                                 acc)
1209                           (setq pairs (cddr pairs)))
1210                         (apply 'concat acc)))
1211            (k-one@ (name &optional later) (tok+val 'to-one@ name
1212                                                    (if later
1213                                                        (lambda () t)
1214                                                      'gather))))
1215       (save-excursion
1216         (goto-char (point-min))
1217         ;; headers
1218         (setq context 'headers)
1219         (flet ((hpush (name &optional proc)
1220                       (push (k-semi name proc) headers)))
1221           (hpush 'head)
1222           (when (at 'branch)
1223             (hpush 'branch))
1224           (hpush 'access)
1225           (hpush 'symbols
1226                  (lambda ()
1227                    (mapcar (lambda (together)
1228                              (let ((two (split-string together ":")))
1229                                (setcar two (intern (car two)))
1230                                (setcdr two (cadr two))
1231                                two))
1232                            (split-string
1233                             (buffer-substring-no-properties b e)))))
1234           (hpush 'locks))
1235         (push `(strict . ,(when (at 'strict)
1236                             (search-forward ";")
1237                             t))
1238               headers)
1239         (when (at 'comment)
1240           (push (k-one@ 'comment) headers)
1241           (search-forward ";"))
1242         (when (at 'expand)
1243           (push (k-one@ 'expand) headers)
1244           (search-forward ";"))
1245         (setq headers (nreverse headers))
1246         ;; rev headers
1247         (sw) (setq context 'rev-headers)
1248         (while (looking-at "[0-9]")
1249           (push `(,(to-eol)
1250                   ,(k-semi 'date
1251                            (lambda ()
1252                              (let ((ls (mapcar 'string-to-number
1253                                                (split-string
1254                                                 (buffer-substring-no-properties
1255                                                  b e)
1256                                                 "\\."))))
1257                                ;; Hack the year -- verified to be the
1258                                ;; same algorithm used in RCS 5.7.
1259                                (when (< (car ls) 100)
1260                                  (setcar ls (+ 1900 (car ls))))
1261                                (apply 'encode-time (nreverse ls)))))
1262                   ,@(mapcar 'k-semi '(author state))
1263                   ,(k-semi 'branches
1264                            (lambda ()
1265                              (split-string
1266                               (buffer-substring-no-properties b e))))
1267                   ,(k-semi 'next))
1268                 revs)
1269           (sw))
1270         (setq revs (nreverse revs))
1271         ;; desc
1272         (sw) (setq context 'desc
1273                    desc (k-one@ 'desc))
1274         ;; rev bodies
1275         (let (acc
1276               ;; Element of `revs' that initially holds only header info.
1277               ;; "Pairwise combination" occurs when we add body info.
1278               rev
1279               ;; Components of the editing commands (aside from the actual
1280               ;; text) that comprise the `text' printed representations
1281               ;; (not including the "head" revision).
1282               cmd start act
1283               ;; Ascending (reversed) `@-holes' which the internal func
1284               ;; `incg' pops to effect incremental gathering.
1285               asc
1286               ;; Function to extract text (for the `a' command), either
1287               ;; `incg' or `buffer-substring-no-properties'.  (This is
1288               ;; for speed; strictly speaking, it is sufficient to use
1289               ;; only the former since it behaves identically to the
1290               ;; latter in the absense of "@@".)
1291               sub)
1292           (flet ((incg (beg end) (let ((b beg) (e end) @-holes)
1293                                    (while (and asc (< (car asc) e))
1294                                      (push (pop asc) @-holes))
1295                                    ;; Self-deprecate when work is done.
1296                                    ;; Folding many dimensions into one.
1297                                    ;; Thanks B.Mandelbrot, for complex sum.
1298                                    ;; O beauteous math! --the Unvexed Bum
1299                                    (unless asc
1300                                      (setq sub 'buffer-substring-no-properties))
1301                                    (gather))))
1302             (while (and (sw)
1303                         (not (eobp))
1304                         (setq context (to-eol)
1305                               rev (or (assoc context revs)
1306                                       (error "Rev `%s' has body but no head"
1307                                              context))))
1308               (push (k-one@ 'log) (cdr rev))
1309               ;; For rev body `text' tags, delay translation slightly...
1310               (push (k-one@ 'text t) (cdr rev))
1311               ;; ... until we decide which tag and value is appropriate to
1312               ;; collect.  For the "head" revision, compute the value of the
1313               ;; `text' printed representation by simple `gather'.  For all
1314               ;; other revisions, replace the `text' tag+value with `:insn'
1315               ;; plus value, always scanning in-place.
1316               (if (string= context (cdr (assq 'head headers)))
1317                   (setcdr (cadr rev) (gather))
1318                 (if @-holes
1319                     (setq asc (nreverse @-holes)
1320                           sub 'incg)
1321                   (setq sub 'buffer-substring-no-properties))
1322                 (goto-char b)
1323                 (setq acc nil)
1324                 (while (< (point) e)
1325                   (forward-char 1)
1326                   (setq cmd (char-before)
1327                         start (read (current-buffer))
1328                         act (read (current-buffer)))
1329                   (forward-char 1)
1330                   (push (case cmd
1331                           (?d
1332                            ;; `d' means "delete lines".
1333                            ;; For Emacs spirit, we use `k' for "kill".
1334                            `(,start k ,act))
1335                           (?a
1336                            ;; `a' means "append after this line" but
1337                            ;; internally we normalize it so that START
1338                            ;; specifies the actual line for insert, thus
1339                            ;; requiring less hair in the realization algs.
1340                            ;; For Emacs spirit, we use `i' for "insert".
1341                            `(,(1+ start) i
1342                              ,(funcall sub (point) (progn (forward-line act)
1343                                                           (point)))))
1344                           (t (error "Bad command `%c' in `text' for rev `%s'"
1345                                     cmd context)))
1346                         acc))
1347                 (goto-char (1+ e))
1348                 (setcar (cdr rev) (cons :insn acc)))))))
1349       ;; rv
1350       `((headers ,desc ,@headers)
1351         (revisions ,@revs)))))
1352
1353 (provide 'vc-rcs)
1354
1355 ;; arch-tag: 759b4916-5b0d-431d-b647-b185b8c652cf
1356 ;;; vc-rcs.el ends here