1 ;;; vc.el --- drive a version-control system from within Emacs
3 ;; Copyright (C) 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
5 ;; Author: Eric S. Raymond <esr@snark.thyrsus.com>
8 ;; Per Cederqvist <ceder@lysator.liu.edu>
9 ;; Andre Spiegel <spiegel@berlin.informatik.uni-stuttgart.de>
11 ;; This file is part of GNU Emacs.
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 2, or (at your option)
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.
23 ;; You should have received a copy of the GNU General Public License
24 ;; along with GNU Emacs; see the file COPYING. If not, write to
25 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
29 ;; This mode is fully documented in the Emacs user's manual.
31 ;; This was designed and implemented by Eric Raymond <esr@snark.thyrsus.com>.
32 ;; Paul Eggert <eggert@twinsun.com>, Sebastian Kremer <sk@thp.uni-koeln.de>,
33 ;; and Richard Stallman contributed valuable criticism, support, and testing.
34 ;; CVS support was added by Per Cederqvist <ceder@lysator.liu.se>
37 ;; Supported version-control systems presently include SCCS, RCS, and CVS.
39 ;; Some features will not work with old RCS versions. Where
40 ;; appropriate, VC finds out which version you have, and allows or
41 ;; disallows those features (stealing locks, for example, works only
42 ;; from 5.6.2 onwards).
43 ;; Even initial checkins will fail if your RCS version is so old that ci
44 ;; doesn't understand -t-; this has been known to happen to people running
47 ;; You can support the RCS -x option by adding pairs to the
48 ;; vc-master-templates list.
50 ;; Proper function of the SCCS diff commands requires the shellscript vcdiff
51 ;; to be installed somewhere on Emacs's path for executables.
53 ;; If your site uses the ChangeLog convention supported by Emacs, the
54 ;; function vc-comment-to-change-log should prove a useful checkin hook.
56 ;; This code depends on call-process passing back the subprocess exit
57 ;; status. Thus, you need Emacs 18.58 or later to run it. For the
58 ;; vc-directory command to work properly as documented, you need 19.
59 ;; You also need Emacs 19's ring.el.
61 ;; The vc code maintains some internal state in order to reduce expensive
62 ;; version-control operations to a minimum. Some names are only computed
63 ;; once. If you perform version control operations with RCS/SCCS/CVS while
64 ;; vc's back is turned, or move/rename master files while vc is running,
65 ;; vc may get seriously confused. Don't do these things!
67 ;; Developer's notes on some concurrency issues are included at the end of
74 (eval-when-compile (require 'dired)) ; for dired-map-over-marks macro
76 (if (not (assoc 'vc-parent-buffer minor-mode-alist))
77 (setq minor-mode-alist
78 (cons '(vc-parent-buffer vc-parent-buffer-name)
81 ;; To implement support for a new version-control system, add another
82 ;; branch to the vc-backend-dispatch macro and fill it in in each
83 ;; call. The variable vc-master-templates in vc-hooks.el will also
86 (defmacro vc-backend-dispatch (f s r c)
87 "Execute FORM1, FORM2 or FORM3 for SCCS, RCS or CVS respectively.
88 If FORM3 is `RCS', use FORM2 for CVS as well as RCS.
89 \(CVS shares some code with RCS)."
90 (list 'let (list (list 'type (list 'vc-backend f)))
92 (list (list 'eq 'type (quote 'SCCS)) s) ;; SCCS
93 (list (list 'eq 'type (quote 'RCS)) r) ;; RCS
94 (list (list 'eq 'type (quote 'CVS)) ;; CVS
98 ;; General customization
100 (defvar vc-suppress-confirm nil
101 "*If non-nil, treat user as expert; suppress yes-no prompts on some things.")
102 (defvar vc-initial-comment nil
103 "*Prompt for initial comment when a file is registered.")
104 (defvar vc-command-messages nil
105 "*Display run messages from back-end commands.")
106 (defvar vc-checkin-switches nil
107 "*Extra switches passed to the checkin program by \\[vc-checkin].")
108 (defvar vc-checkout-switches nil
109 "*Extra switches passed to the checkout program by \\[vc-checkout].")
110 (defvar vc-directory-exclusion-list '("SCCS" "RCS" "CVS")
111 "*Directory names ignored by functions that recursively walk file trees.")
113 (defconst vc-maximum-comment-ring-size 32
114 "Maximum number of saved comments in the comment ring.")
116 ;;; This is duplicated in diff.el.
117 (defvar diff-switches "-c"
118 "*A string or list of strings specifying switches to be be passed to diff.")
121 (defvar vc-checkin-hook nil
122 "*List of functions called after a checkin is done. See `run-hooks'.")
124 (defvar vc-make-buffer-writable-hook nil
125 "*List of functions called when a buffer is made writable. See `run-hooks.'
126 This hook is only used when the version control system is CVS. It
127 might be useful for sites who uses locking with CVS, or who uses link
128 farms to gold trees.")
130 ;; Header-insertion hair
132 (defvar vc-header-alist
133 '((SCCS "\%W\%") (RCS "\$Id\$") (CVS "\$Id\$"))
134 "*Header keywords to be inserted when `vc-insert-headers' is executed.")
135 (defvar vc-static-header-alist
137 "\n#ifndef lint\nstatic char vcid[] = \"\%s\";\n#endif /* lint */\n"))
138 "*Associate static header string templates with file types. A \%s in the
139 template is replaced with the first string associated with the file's
140 version-control type in `vc-header-alist'.")
142 (defvar vc-comment-alist
143 '((nroff-mode ".\\\"" ""))
144 "*Special comment delimiters to be used in generating vc headers only.
145 Add an entry in this list if you need to override the normal comment-start
146 and comment-end variables. This will only be necessary if the mode language
147 is sensitive to blank lines.")
149 ;; Default is to be extra careful for super-user.
150 (defvar vc-checkout-carefully (= (user-uid) 0)
151 "*Non-nil means be extra-careful in checkout.
152 Verify that the file really is not locked
153 and that its contents match what the master file says.")
155 (defvar vc-rcs-release nil
156 "*The release number of your RCS installation, as a string.
157 If nil, VC itself computes this value when it is first needed.")
159 (defvar vc-sccs-release nil
160 "*The release number of your SCCS installation, as a string.
161 If nil, VC itself computes this value when it is first needed.")
163 (defvar vc-cvs-release nil
164 "*The release number of your SCCS installation, as a string.
165 If nil, VC itself computes this value when it is first needed.")
167 ;; Variables the user doesn't need to know about.
168 (defvar vc-log-entry-mode nil)
169 (defvar vc-log-operation nil)
170 (defvar vc-log-after-operation-hook nil)
171 (defvar vc-checkout-writable-buffer-hook 'vc-checkout-writable-buffer)
172 ;; In a log entry buffer, this is a local variable
173 ;; that points to the buffer for which it was made
174 ;; (either a file, or a VC dired buffer).
175 (defvar vc-parent-buffer nil)
176 (defvar vc-parent-buffer-name nil)
179 (defvar vc-log-version)
181 (defconst vc-name-assoc-file "VC-names")
183 (defvar vc-dired-mode nil)
184 (make-variable-buffer-local 'vc-dired-mode)
186 (defvar vc-comment-ring nil)
187 (defvar vc-comment-ring-index nil)
188 (defvar vc-last-comment-match nil)
190 ;; Back-portability to Emacs 18
192 (defun file-executable-p-18 (f)
193 (let ((modes (file-modes f)))
194 (and modes (not (zerop (logand 292))))))
196 (defun file-regular-p-18 (f)
197 (let ((attributes (file-attributes f)))
198 (and attributes (not (car attributes)))))
200 ; Conditionally rebind some things for Emacs 18 compatibility
201 (if (not (boundp 'minor-mode-map-alist))
203 (setq compilation-old-error-list nil)
204 (fset 'file-executable-p 'file-executable-p-18)
205 (fset 'shrink-window-if-larger-than-buffer 'beginning-of-buffer)
208 (if (not (fboundp 'file-regular-p))
209 (fset 'file-regular-p 'file-regular-p-18))
211 ;;; Find and compare backend releases
213 (defun vc-backend-release (backend)
214 ;; Returns which backend release is installed on this system.
218 (and (zerop (vc-do-command nil 2 "rcs" nil nil "-V"))
220 (set-buffer (get-buffer "*vc*"))
222 (car (vc-parse-buffer
223 '(("^RCS version \\([0-9.]+ *.*\\)" 1)))))))
224 (setq vc-rcs-release 'unknown)))
227 (and (zerop (vc-do-command nil 1 "cvs" nil nil "-v"))
229 (set-buffer (get-buffer "*vc*"))
231 (car (vc-parse-buffer
232 '(("^Concurrent Versions System (CVS) \\([0-9.]+\\)"
234 (setq vc-cvs-release 'unknown)))
238 (defun vc-release-greater-or-equal (r1 r2)
239 ;; Compare release numbers, represented as strings.
240 ;; Release components are assumed cardinal numbers, not decimal
241 ;; fractions (5.10 is a higher release than 5.9). Omitted fields
242 ;; are considered lower (5.6.7 is earlier than 5.6.7.1).
243 ;; Comparison runs till the end of the string is found, or a
244 ;; non-numeric component shows up (5.6.7 is earlier than "5.6.7 beta",
245 ;; which is probably not what you want in some cases).
246 ;; This code is suitable for existing RCS release numbers.
247 ;; CVS releases are handled reasonably, too (1.3 < 1.4* < 1.5).
250 (or (and (string-match "^\\.?\\([0-9]+\\)" r1)
251 (setq i1 (match-end 0))
252 (setq v1 (string-to-number (match-string 1 r1)))
253 (or (and (string-match "^\\.?\\([0-9]+\\)" r2)
254 (setq i2 (match-end 0))
255 (setq v2 (string-to-number (match-string 1 r2)))
256 (if (> v1 v2) (throw 'done t)
257 (if (< v1 v2) (throw 'done nil)
259 (vc-release-greater-or-equal
261 (substring r2 i2)))))))
263 (or (and (string-match "^\\.?\\([0-9]+\\)" r2)
267 (defun vc-backend-release-p (backend release)
268 ;; Return t if we have RELEASE of BACKEND or better
269 (let (i r (ri 0) (ii 0) is rs (installation (vc-backend-release backend)))
270 (if (not (eq installation 'unknown))
272 ((or (eq backend 'RCS) (eq backend 'CVS))
273 (vc-release-greater-or-equal installation release))))))
275 ;;; functions that operate on RCS revision numbers
277 (defun vc-trunk-p (rev)
278 ;; return t if REV is a revision on the trunk
279 (not (eq nil (string-match "\\`[0-9]+\\.[0-9]+\\'" rev))))
281 (defun vc-branch-part (rev)
282 ;; return the branch part of a revision number REV
283 (substring rev 0 (string-match "\\.[0-9]+\\'" rev)))
285 ;; File property caching
287 (defun vc-clear-context ()
288 "Clear all cached file properties and the comment ring."
290 (fillarray vc-file-prop-obarray nil)
291 ;; Note: there is potential for minor lossage here if there is an open
292 ;; log buffer with a nonzero local value of vc-comment-ring-index.
293 (setq vc-comment-ring nil))
295 (defun vc-file-clear-masterprops (file)
296 ;; clear all properties of FILE that were retrieved
297 ;; from the master file
298 (vc-file-setprop file 'vc-latest-version nil)
299 (vc-file-setprop file 'vc-your-latest-version nil)
300 (vc-backend-dispatch file
302 (vc-file-setprop file 'vc-master-locks nil))
304 (vc-file-setprop file 'vc-default-branch nil)
305 (vc-file-setprop file 'vc-head-version nil)
306 (vc-file-setprop file 'vc-master-workfile-version nil)
307 (vc-file-setprop file 'vc-master-locks nil))
309 (vc-file-setprop file 'vc-cvs-status nil))))
311 (defun vc-head-version (file)
312 ;; Return the RCS head version of FILE
313 (cond ((vc-file-getprop file 'vc-head-version))
314 (t (vc-fetch-master-properties file)
315 (vc-file-getprop file 'vc-head-version))))
317 ;; Random helper functions
319 (defun vc-latest-on-branch-p (file)
320 ;; return t iff the current workfile version of FILE is
321 ;; the latest on its branch.
322 (vc-backend-dispatch file
324 (string= (vc-workfile-version file) (vc-latest-version file))
326 (let ((workfile-version (vc-workfile-version file)) tip-version)
327 (if (vc-trunk-p workfile-version)
329 ;; Re-fetch the head version number. This is to make
330 ;; sure that no-one has checked in a new version behind
332 (vc-fetch-master-properties file)
333 (string= (vc-file-getprop file 'vc-head-version)
335 ;; If we are not on the trunk, we need to examine the
336 ;; whole current branch. (vc-master-workfile-version
337 ;; is not what we need.)
339 (set-buffer (get-buffer-create "*vc-info*"))
340 (vc-insert-file (vc-name file) "^desc")
341 (setq tip-version (car (vc-parse-buffer (list (list
342 (concat "^\\(" (regexp-quote (vc-branch-part workfile-version))
343 "\\.[0-9]+\\)\ndate[ \t]+\\([0-9.]+\\);") 1 2)))))
344 (if (get-buffer "*vc-info*")
345 (kill-buffer (get-buffer "*vc-info*")))
346 (string= tip-version workfile-version))))
350 (defun vc-registration-error (file)
352 (error "File %s is not under version control" file)
353 (error "Buffer %s is not associated with a file" (buffer-name))))
355 (defvar vc-binary-assoc nil)
357 (defun vc-find-binary (name)
358 "Look for a command anywhere on the subprocess-command search path."
359 (or (cdr (assoc name vc-binary-assoc))
365 (let ((full (concat s "/" name)))
366 (if (file-executable-p full)
368 (setq vc-binary-assoc
369 (cons (cons name full) vc-binary-assoc))
370 (throw 'found full)))))))
374 (defun vc-do-command (buffer okstatus command file last &rest flags)
375 "Execute a version-control command, notifying user and checking for errors.
376 Output from COMMAND goes to BUFFER, or *vc* if BUFFER is nil.
377 The command is successful if its exit status does not exceed OKSTATUS.
378 The last argument of the command is the master name of FILE if LAST is
379 `MASTER', or the workfile of FILE if LAST is `WORKFILE'; this is appended
380 to an optional list of FLAGS."
381 (and file (setq file (expand-file-name file)))
382 (if (not buffer) (setq buffer "*vc*"))
383 (if vc-command-messages
384 (message "Running %s on %s..." command file))
385 (let ((obuf (current-buffer)) (camefrom (current-buffer))
387 (vc-file (and file (vc-name file)))
388 (olddir default-directory)
390 (set-buffer (get-buffer-create buffer))
391 (set (make-local-variable 'vc-parent-buffer) camefrom)
392 (set (make-local-variable 'vc-parent-buffer-name)
393 (concat " from " (buffer-name camefrom)))
394 (setq default-directory olddir)
399 (function (lambda (s) (and s (setq squeezed (append squeezed (list s))))))
401 (if (and vc-file (eq last 'MASTER))
402 (setq squeezed (append squeezed (list vc-file))))
403 (if (eq last 'WORKFILE)
405 (let* ((pwd (expand-file-name default-directory))
406 (preflen (length pwd)))
407 (if (string= (substring file 0 preflen) pwd)
408 (setq file (substring file preflen))))
409 (setq squeezed (append squeezed (list file)))))
410 (let ((exec-path (append vc-path exec-path))
411 ;; Add vc-path to PATH for the execution of this command.
413 (cons (concat "PATH=" (getenv "PATH")
415 (mapconcat 'identity vc-path path-separator))
416 process-environment)))
417 (setq status (apply 'call-process command nil t nil squeezed)))
418 (goto-char (point-max))
419 (set-buffer-modified-p nil)
421 (if (or (not (integerp status)) (< okstatus status))
423 (pop-to-buffer buffer)
424 (goto-char (point-min))
425 (shrink-window-if-larger-than-buffer)
426 (error "Running %s...FAILED (%s)" command
427 (if (integerp status)
428 (format "status %d" status)
431 (if vc-command-messages
432 (message "Running %s...OK" command))
438 ;;; Save a bit of the text around POSN in the current buffer, to help
439 ;;; us find the corresponding position again later. This works even
440 ;;; if all markers are destroyed or corrupted.
441 ;;; A lot of this was shamelessly lifted from Sebastian Kremer's rcs.el mode.
442 (defun vc-position-context (posn)
445 (buffer-substring posn
446 (min (point-max) (+ posn 100)))))
448 ;;; Return the position of CONTEXT in the current buffer, or nil if we
449 ;;; couldn't find it.
450 (defun vc-find-position-by-context (context)
451 (let ((context-string (nth 2 context)))
452 (if (equal "" context-string)
455 (let ((diff (- (nth 1 context) (buffer-size))))
456 (if (< diff 0) (setq diff (- diff)))
457 (goto-char (nth 0 context))
458 (if (or (search-forward context-string nil t)
459 ;; Can't use search-backward since the match may continue
461 (progn (goto-char (- (point) diff (length context-string)))
462 ;; goto-char doesn't signal an error at
463 ;; beginning of buffer like backward-char would
464 (search-forward context-string nil t)))
465 ;; to beginning of OSTRING
466 (- (point) (length context-string))))))))
468 (defun vc-buffer-context ()
469 ;; Return a list '(point-context mark-context reparse); from which
470 ;; vc-restore-buffer-context can later restore the context.
471 (let ((point-context (vc-position-context (point)))
472 ;; Use mark-marker to avoid confusion in transient-mark-mode.
473 (mark-context (if (eq (marker-buffer (mark-marker)) (current-buffer))
474 (vc-position-context (mark-marker))))
475 ;; Make the right thing happen in transient-mark-mode.
477 ;; We may want to reparse the compilation buffer after revert
478 (reparse (and (boundp 'compilation-error-list) ;compile loaded
479 (let ((curbuf (current-buffer)))
480 ;; Construct a list; each elt is nil or a buffer
481 ;; iff that buffer is a compilation output buffer
482 ;; that contains markers into the current buffer.
488 compilation-old-error-list
489 compilation-error-list))
490 (buffer-error-marked-p nil))
491 (while (and (consp errors)
492 (not buffer-error-marked-p))
493 (and (markerp (cdr (car errors)))
497 (setq buffer-error-marked-p t))
498 (setq errors (cdr errors)))
499 (if buffer-error-marked-p buffer))))
501 (list point-context mark-context reparse)))
503 (defun vc-restore-buffer-context (context)
504 ;; Restore point/mark, and reparse any affected compilation buffers.
505 ;; CONTEXT is that which vc-buffer-context returns.
506 (let ((point-context (nth 0 context))
507 (mark-context (nth 1 context))
508 (reparse (nth 2 context)))
509 ;; Reparse affected compilation buffers.
513 (set-buffer (car reparse))
514 (let ((compilation-last-buffer (current-buffer)) ;select buffer
515 ;; Record the position in the compilation buffer of
516 ;; the last error next-error went to.
517 (error-pos (marker-position
518 (car (car-safe compilation-error-list)))))
519 ;; Reparse the error messages as far as they were parsed before.
520 (compile-reinitialize-errors '(4) compilation-parsing-end)
521 ;; Move the pointer up to find the error we were at before
522 ;; reparsing. Now next-error should properly go to the next one.
523 (while (and compilation-error-list
524 (/= error-pos (car (car compilation-error-list))))
525 (setq compilation-error-list (cdr compilation-error-list))))))
526 (setq reparse (cdr reparse)))
528 ;; Restore point and mark
529 (let ((new-point (vc-find-position-by-context point-context)))
530 (if new-point (goto-char new-point)))
532 (let ((new-mark (vc-find-position-by-context mark-context)))
533 (if new-mark (set-mark new-mark))))))
535 (defun vc-revert-buffer1 (&optional arg no-confirm)
536 ;; Revert buffer, try to keep point and mark where user expects them in spite
537 ;; of changes because of expanded version-control key words.
538 ;; This is quite important since otherwise typeahead won't work as expected.
541 (let ((context (vc-buffer-context)))
542 (revert-buffer arg no-confirm)
543 (vc-restore-buffer-context context)))
546 (defun vc-buffer-sync (&optional not-urgent)
547 ;; Make sure the current buffer and its working file are in sync
548 ;; NOT-URGENT means it is ok to continue if the user says not to save.
549 (if (buffer-modified-p)
550 (if (or vc-suppress-confirm
551 (y-or-n-p (format "Buffer %s modified; save it? " (buffer-name))))
555 (error "Aborted")))))
558 (defun vc-workfile-unchanged-p (file &optional want-differences-if-changed)
559 ;; Has the given workfile changed since last checkout?
560 (let ((checkout-time (vc-file-getprop file 'vc-checkout-time))
561 (lastmod (nth 5 (file-attributes file))))
562 (or (equal checkout-time lastmod)
563 (and (or (not checkout-time) want-differences-if-changed)
564 (let ((unchanged (zerop (vc-backend-diff file nil nil
565 (not want-differences-if-changed)))))
566 ;; 0 stands for an unknown time; it can't match any mod time.
567 (vc-file-setprop file 'vc-checkout-time (if unchanged lastmod 0))
570 (defun vc-next-action-on-file (file verbose &optional comment)
571 ;;; If comment is specified, it will be used as an admin or checkin comment.
572 (let ((vc-file (vc-name file))
573 (vc-type (vc-backend file))
574 owner version buffer)
577 ;; if there is no master file corresponding, create one
579 (vc-register verbose comment)
580 (if vc-initial-comment
581 (setq vc-log-after-operation-hook
582 'vc-checkout-writable-buffer-hook)
583 (vc-checkout-writable-buffer file)))
585 ;; CVS: changes to the master file need to be
586 ;; merged back into the working file
587 ((and (eq vc-type 'CVS)
588 (or (eq (vc-cvs-status file) 'needs-checkout)
589 (eq (vc-cvs-status file) 'needs-merge)))
590 (if (or vc-dired-mode
592 (format "%s is not up-to-date. Merge in changes now? "
596 (and (setq buffer (get-file-buffer file))
597 (buffer-modified-p buffer)
598 (switch-to-buffer-other-window buffer)
600 (setq buffer (current-buffer))
602 (if (and buffer (buffer-modified-p buffer)
605 "Buffer %s modified; merge file on disc anyhow? "
606 (buffer-name buffer)))))
607 (error "Merge aborted"))
608 (if (not (zerop (vc-backend-merge-news file)))
609 ;; Overlaps detected - what now? Should use some
610 ;; fancy RCS conflict resolving package, or maybe
611 ;; emerge, but for now, simply warn the user with a
613 (message "Conflicts detected!"))
615 (vc-resynch-buffer file t (not (buffer-modified-p buffer)))))
616 (error "%s needs update" (buffer-name))))
618 ;; if there is no lock on the file, assert one and get it
619 ((not (setq owner (vc-locking-user file)))
620 (if (and vc-checkout-carefully
621 (not (vc-workfile-unchanged-p file t)))
622 (if (save-window-excursion
623 (pop-to-buffer "*vc-diff*")
624 (goto-char (point-min))
625 (insert-string (format "Changes to %s since last lock:\n\n"
629 (concat "File has unlocked changes, "
630 "claim lock retaining changes? ")))
631 (progn (vc-backend-steal file)
633 (if (not (yes-or-no-p "Revert to checked-in version, instead? "))
634 (error "Checkout aborted.")
635 (vc-revert-buffer1 t t)
636 (vc-checkout-writable-buffer file))
639 (if (not (eq vc-type 'SCCS))
640 (vc-checkout file nil
641 (read-string "Branch or version to move to: "))
642 (error "Sorry, this is not implemented for SCCS."))
643 (if (vc-latest-on-branch-p file)
644 (vc-checkout-writable-buffer file)
646 "This is not the latest version. Really lock it? ")
647 (vc-checkout-writable-buffer file)
648 (if (yes-or-no-p "Lock the latest version instead? ")
649 (vc-checkout-writable-buffer file
650 (if (vc-trunk-p (vc-workfile-version file))
651 "" ;; this means check out latest on trunk
652 (vc-branch-part (vc-workfile-version file)))))))
655 ;; a checked-out version exists, but the user may not own the lock
656 ((and (not (eq vc-type 'CVS))
657 (not (string-equal owner (user-login-name))))
659 (error "Sorry, you can't steal the lock on %s this way" file))
660 (and (eq vc-type 'RCS)
661 (not (vc-backend-release-p 'RCS "5.6.2"))
662 (error "File is locked by %s." owner))
665 (if verbose (read-string "Version to steal: ")
666 (vc-workfile-version file))
669 ;; OK, user owns the lock on the file
672 (find-file-other-window file)
675 ;; give luser a chance to save before checking in.
678 ;; Revert if file is unchanged and buffer is too.
679 ;; If buffer is modified, that means the user just said no
680 ;; to saving it; in that case, don't revert,
681 ;; because the user might intend to save
682 ;; after finishing the log entry.
683 (if (and (vc-workfile-unchanged-p file)
684 (not (buffer-modified-p)))
685 ;; DO NOT revert the file without asking the user!
687 ((yes-or-no-p "Revert to master version? ")
688 (vc-backend-revert file)
689 (vc-resynch-window file t t)))
691 ;; user may want to set nonstandard parameters
693 (setq version (read-string "New version level: ")))
695 ;; OK, let's do the checkin
696 (vc-checkin file version comment)
699 (defun vc-next-action-dired (file rev comment)
700 ;; Do a vc-next-action-on-file on all the marked files, possibly
701 ;; passing on the log comment we've just entered.
702 (let ((configuration (current-window-configuration))
703 (dired-buffer (current-buffer))
704 (dired-dir default-directory))
705 (dired-map-over-marks
706 (let ((file (dired-get-filename)) p)
707 (message "Processing %s..." file)
708 ;; Adjust the default directory so that checkouts
709 ;; go to the right place.
710 (setq default-directory (file-name-directory file))
711 (vc-next-action-on-file file nil comment)
712 (set-buffer dired-buffer)
713 (setq default-directory dired-dir)
714 (vc-dired-update-line file)
715 (set-window-configuration configuration)
716 (message "Processing %s...done" file))
719 ;; Here's the major entry point.
722 (defun vc-next-action (verbose)
723 "Do the next logical checkin or checkout operation on the current file.
724 If you call this from within a VC dired buffer with no files marked,
725 it will operate on the file in the current line.
726 If you call this from within a VC dired buffer, and one or more
727 files are marked, it will accept a log message and then operate on
728 each one. The log message will be used as a comment for any register
729 or checkin operations, but ignored when doing checkouts. Attempted
730 lock steals will raise an error.
731 A prefix argument lets you specify the version number to use.
733 For RCS and SCCS files:
734 If the file is not already registered, this registers it for version
735 control and then retrieves a writable, locked copy for editing.
736 If the file is registered and not locked by anyone, this checks out
737 a writable and locked file ready for editing.
738 If the file is checked out and locked by the calling user, this
739 first checks to see if the file has changed since checkout. If not,
740 it performs a revert.
741 If the file has been changed, this pops up a buffer for entry
742 of a log message; when the message has been entered, it checks in the
743 resulting changes along with the log message as change commentary. If
744 the variable `vc-keep-workfiles' is non-nil (which is its default), a
745 read-only copy of the changed file is left in place afterwards.
746 If the file is registered and locked by someone else, you are given
747 the option to steal the lock.
750 If the file is not already registered, this registers it for version
751 control. This does a \"cvs add\", but no \"cvs commit\".
752 If the file is added but not committed, it is committed.
753 If your working file is changed, but the repository file is
754 unchanged, this pops up a buffer for entry of a log message; when the
755 message has been entered, it checks in the resulting changes along
756 with the logmessage as change commentary. A writable file is retained.
757 If the repository file is changed, you are asked if you want to
758 merge in the changes into your working copy."
763 (let ((files (dired-get-marked-files)))
766 (function (lambda (f)
767 (if (eq (vc-backend f) 'CVS)
768 (if (or (eq (vc-cvs-status f) 'locally-modified)
769 (eq (vc-cvs-status f) 'locally-added))
771 (if (vc-locking-user f) "@" ""))))
773 (vc-next-action-dired nil nil "dummy")
774 (vc-start-entry nil nil nil
775 "Enter a change comment for the marked files."
776 'vc-next-action-dired))
778 (while vc-parent-buffer
779 (pop-to-buffer vc-parent-buffer))
781 (vc-next-action-on-file buffer-file-name verbose)
782 (vc-registration-error nil))))
784 ;;; These functions help the vc-next-action entry point
786 (defun vc-checkout-writable-buffer (&optional file rev)
787 "Retrieve a writable copy of the latest version of the current buffer's file."
788 (vc-checkout (or file (buffer-file-name)) t rev)
792 (defun vc-register (&optional override comment)
793 "Register the current file into your version-control system."
796 (error "No visited file"))
797 (let ((master (vc-name buffer-file-name)))
798 (and master (file-exists-p master)
799 (error "This file is already registered"))
801 (not (y-or-n-p "Previous master file has vanished. Make a new one? "))
802 (error "This file is already registered")))
803 ;; Watch out for new buffers of size 0: the corresponding file
804 ;; does not exist yet, even though buffer-modified-p is nil.
805 (if (and (not (buffer-modified-p))
806 (zerop (buffer-size))
807 (not (file-exists-p buffer-file-name)))
808 (set-buffer-modified-p t))
810 (cond ((not vc-make-backup-files)
811 ;; inhibit backup for this buffer
812 (make-local-variable 'backup-inhibited)
813 (setq backup-inhibited t)))
818 (format "Initial version level for %s: " buffer-file-name))))
821 (defun vc-resynch-window (file &optional keep noquery)
822 ;; If the given file is in the current buffer,
823 ;; either revert on it so we see expanded keyworks,
824 ;; or unvisit it (depending on vc-keep-workfiles)
825 ;; NOQUERY if non-nil inhibits confirmation for reverting.
826 ;; NOQUERY should be t *only* if it is known the only difference
827 ;; between the buffer and the file is due to RCS rather than user editing!
828 (and (string= buffer-file-name file)
831 ;; temporarily remove vc-find-file-hook, so that
832 ;; we don't lose the properties
833 (remove-hook 'find-file-hooks 'vc-find-file-hook)
834 (vc-revert-buffer1 t noquery)
835 (add-hook 'find-file-hooks 'vc-find-file-hook)
836 (vc-mode-line buffer-file-name))
837 (kill-buffer (current-buffer)))))
839 (defun vc-resynch-buffer (file &optional keep noquery)
840 ;; if FILE is currently visited, resynch its buffer
841 (let ((buffer (get-file-buffer file)))
845 (vc-resynch-window file keep noquery)))))
847 (defun vc-start-entry (file rev comment msg action &optional after-hook)
848 ;; Accept a comment for an operation on FILE revision REV. If COMMENT
849 ;; is nil, pop up a VC-log buffer, emit MSG, and set the
850 ;; action on close to ACTION; otherwise, do action immediately.
851 ;; Remember the file's buffer in vc-parent-buffer (current one if no file).
852 ;; AFTER-HOOK specifies the local value for vc-log-operation-hook.
853 (let ((parent (if file (find-file-noselect file) (current-buffer))))
855 (set-buffer (get-buffer-create "*VC-log*"))
856 (pop-to-buffer (get-buffer-create "*VC-log*")))
857 (set (make-local-variable 'vc-parent-buffer) parent)
858 (set (make-local-variable 'vc-parent-buffer-name)
859 (concat " from " (buffer-name vc-parent-buffer)))
860 (if file (vc-mode-line file))
862 (make-local-variable 'vc-log-after-operation-hook)
864 (setq vc-log-after-operation-hook after-hook))
865 (setq vc-log-operation action)
866 (setq vc-log-file file)
867 (setq vc-log-version rev)
872 (vc-finish-logentry t)
874 (vc-finish-logentry nil)))
875 (message "%s Type C-c C-c when done." msg))))
877 (defun vc-admin (file rev &optional comment)
878 "Check a file into your version-control system.
879 FILE is the unmodified name of the file. REV should be the base version
880 level to check it in under. COMMENT, if specified, is the checkin comment."
881 (vc-start-entry file rev
882 (or comment (not vc-initial-comment))
883 "Enter initial comment." 'vc-backend-admin
886 (defun vc-checkout (file &optional writable rev)
887 "Retrieve a copy of the latest version of the given file."
888 ;; If ftp is on this system and the name matches the ange-ftp format
889 ;; for a remote file, the user is trying something that won't work.
890 (if (and (string-match "^/[^/:]+:" file) (vc-find-binary "ftp"))
891 (error "Sorry, you can't check out files over FTP"))
892 (vc-backend-checkout file writable rev)
893 (vc-resynch-buffer file t t))
895 (defun vc-steal-lock (file rev &optional owner)
896 "Steal the lock on the current workfile."
897 (let (file-description)
899 (setq owner (vc-locking-user file)))
901 (setq file-description (format "%s:%s" file rev))
902 (setq file-description file))
903 (if (not (y-or-n-p (format "Take the lock on %s from %s? "
904 file-description owner)))
905 (error "Steal cancelled"))
906 (pop-to-buffer (get-buffer-create "*VC-mail*"))
907 (setq default-directory (expand-file-name "~/"))
908 (auto-save-mode auto-save-default)
911 (mail-setup owner (format "Stolen lock on %s" file-description) nil nil nil
912 (list (list 'vc-finish-steal file rev)))
913 (goto-char (point-max))
915 (format "I stole the lock on %s, " file-description)
916 (current-time-string)
918 (message "Please explain why you stole the lock. Type C-c C-c when done.")))
920 ;; This is called when the notification has been sent.
921 (defun vc-finish-steal (file version)
922 (vc-backend-steal file version)
923 (if (get-file-buffer file)
925 (set-buffer (get-file-buffer file))
926 (vc-resynch-window file t t))))
928 (defun vc-checkin (file &optional rev comment)
929 "Check in the file specified by FILE.
930 The optional argument REV may be a string specifying the new version level
931 \(if nil increment the current level). The file is either retained with write
932 permissions zeroed, or deleted (according to the value of `vc-keep-workfiles').
933 If the back-end is CVS, a writable workfile is always kept.
934 COMMENT is a comment string; if omitted, a buffer is
935 popped up to accept a comment."
936 (vc-start-entry file rev comment
937 "Enter a change comment." 'vc-backend-checkin
940 ;;; Here is a checkin hook that may prove useful to sites using the
941 ;;; ChangeLog facility supported by Emacs.
942 (defun vc-comment-to-change-log (&optional whoami file-name)
943 "Enter last VC comment into change log file for current buffer's file.
944 Optional arg (interactive prefix) non-nil means prompt for user name and site.
945 Second arg is file name of change log. \
946 If nil, uses `change-log-default-name'."
947 (interactive (if current-prefix-arg
948 (list current-prefix-arg
949 (prompt-for-change-log-name))))
950 ;; Make sure the defvar for add-log-current-defun-function has been executed
951 ;; before binding it.
953 (let (;; Extract the comment first so we get any error before doing anything.
954 (comment (ring-ref vc-comment-ring 0))
955 ;; Don't let add-change-log-entry insert a defun name.
956 (add-log-current-defun-function 'ignore)
958 ;; Call add-log to do half the work.
959 (add-change-log-entry whoami file-name t t)
960 ;; Insert the VC comment, leaving point before it.
961 (setq end (save-excursion (insert comment) (point-marker)))
962 (if (looking-at "\\s *\\s(")
963 ;; It starts with an open-paren, as in "(foo): Frobbed."
964 ;; So remove the ": " add-log inserted.
966 ;; Canonicalize the white space between the file name and comment.
968 ;; Indent rest of the text the same way add-log indented the first line.
969 (let ((indentation (current-indentation)))
971 (while (< (point) end)
973 (indent-to indentation))
975 ;; Fill the inserted text, preserving open-parens at bol.
976 (let ((paragraph-separate (concat paragraph-separate "\\|\\s *\\s("))
977 (paragraph-start (concat paragraph-start "\\|\\s *\\s(")))
979 (fill-region (point) end))
980 ;; Canonicalize the white space at the end of the entry so it is
981 ;; separated from the next entry by a single blank line.
982 (skip-syntax-forward " " end)
983 (delete-char (- (skip-syntax-backward " ")))
984 (or (eobp) (looking-at "\n\n")
988 (defun vc-finish-logentry (&optional nocomment)
989 "Complete the operation implied by the current log entry."
991 ;; Check and record the comment, if any.
994 (goto-char (point-max))
998 (vc-backend-logentry-check vc-log-file)
999 ;; Record the comment in the comment ring
1000 (if (null vc-comment-ring)
1001 (setq vc-comment-ring (make-ring vc-maximum-comment-ring-size)))
1002 (ring-insert vc-comment-ring (buffer-string))
1004 ;; Sync parent buffer in case the user modified it while editing the comment.
1005 ;; But not if it is a vc-dired buffer.
1007 (set-buffer vc-parent-buffer)
1010 (if (not vc-log-operation) (error "No log operation is pending"))
1011 ;; save the parameters held in buffer-local variables
1012 (let ((log-operation vc-log-operation)
1013 (log-file vc-log-file)
1014 (log-version vc-log-version)
1015 (log-entry (buffer-string))
1016 (after-hook vc-log-after-operation-hook))
1017 ;; Return to "parent" buffer of this checkin and remove checkin window
1018 (pop-to-buffer vc-parent-buffer)
1019 (let ((logbuf (get-buffer "*VC-log*")))
1020 (delete-windows-on logbuf)
1021 (kill-buffer logbuf))
1024 (funcall log-operation
1028 ;; Now make sure we see the expanded headers
1029 (if buffer-file-name
1030 (vc-resynch-window buffer-file-name vc-keep-workfiles t))
1031 (run-hooks after-hook)))
1033 ;; Code for access to the comment ring
1035 (defun vc-previous-comment (arg)
1036 "Cycle backwards through comment history."
1038 (let ((len (ring-length vc-comment-ring)))
1040 (message "Empty comment ring")
1044 ;; Initialize the index on the first use of this command
1045 ;; so that the first M-p gets index 0, and the first M-n gets
1047 (if (null vc-comment-ring-index)
1048 (setq vc-comment-ring-index
1050 (if (< arg 0) 1 0))))
1051 (setq vc-comment-ring-index
1052 (mod (+ vc-comment-ring-index arg) len))
1053 (message "%d" (1+ vc-comment-ring-index))
1054 (insert (ring-ref vc-comment-ring vc-comment-ring-index))))))
1056 (defun vc-next-comment (arg)
1057 "Cycle forwards through comment history."
1059 (vc-previous-comment (- arg)))
1061 (defun vc-comment-search-reverse (str)
1062 "Searches backwards through comment history for substring match."
1063 (interactive "sComment substring: ")
1064 (if (string= str "")
1065 (setq str vc-last-comment-match)
1066 (setq vc-last-comment-match str))
1067 (if (null vc-comment-ring-index)
1068 (setq vc-comment-ring-index -1))
1069 (let ((str (regexp-quote str))
1070 (len (ring-length vc-comment-ring))
1071 (n (1+ vc-comment-ring-index)))
1072 (while (and (< n len) (not (string-match str (ring-ref vc-comment-ring n))))
1075 (vc-previous-comment (- n vc-comment-ring-index)))
1076 (t (error "Not found")))))
1078 (defun vc-comment-search-forward (str)
1079 "Searches forwards through comment history for substring match."
1080 (interactive "sComment substring: ")
1081 (if (string= str "")
1082 (setq str vc-last-comment-match)
1083 (setq vc-last-comment-match str))
1084 (if (null vc-comment-ring-index)
1085 (setq vc-comment-ring-index 0))
1086 (let ((str (regexp-quote str))
1087 (len (ring-length vc-comment-ring))
1088 (n vc-comment-ring-index))
1089 (while (and (>= n 0) (not (string-match str (ring-ref vc-comment-ring n))))
1092 (vc-next-comment (- n vc-comment-ring-index)))
1093 (t (error "Not found")))))
1095 ;; Additional entry points for examining version histories
1098 (defun vc-diff (historic &optional not-urgent)
1099 "Display diffs between file versions.
1100 Normally this compares the current file and buffer with the most recent
1101 checked in version of that file. This uses no arguments.
1102 With a prefix argument, it reads the file name to use
1103 and two version designators specifying which versions to compare."
1106 (set-buffer (find-file-noselect (dired-get-filename))))
1107 (while vc-parent-buffer
1108 (pop-to-buffer vc-parent-buffer))
1110 (call-interactively 'vc-version-diff)
1111 (if (or (null buffer-file-name) (null (vc-name buffer-file-name)))
1113 "There is no version-control master associated with this buffer"))
1114 (let ((file buffer-file-name)
1116 (or (and file (vc-name file))
1117 (vc-registration-error file))
1118 (vc-buffer-sync not-urgent)
1119 (setq unchanged (vc-workfile-unchanged-p buffer-file-name))
1121 (message "No changes to %s since latest version." file)
1122 (vc-backend-diff file)
1123 ;; Ideally, we'd like at this point to parse the diff so that
1124 ;; the buffer effectively goes into compilation mode and we
1125 ;; can visit the old and new change locations via next-error.
1126 ;; Unfortunately, this is just too painful to do. The basic
1127 ;; problem is that the `old' file doesn't exist to be
1128 ;; visited. This plays hell with numerous assumptions in
1129 ;; the diff.el and compile.el machinery.
1130 (pop-to-buffer "*vc-diff*")
1131 (setq default-directory (file-name-directory file))
1132 (if (= 0 (buffer-size))
1135 (message "No changes to %s since latest version." file))
1136 (goto-char (point-min))
1137 (shrink-window-if-larger-than-buffer)))
1140 (defun vc-version-diff (file rel1 rel2)
1141 "For FILE, report diffs between two stored versions REL1 and REL2 of it.
1142 If FILE is a directory, generate diffs between versions for all registered
1143 files in or below it."
1144 (interactive "FFile or directory to diff: \nsOlder version: \nsNewer version: ")
1145 (if (string-equal rel1 "") (setq rel1 nil))
1146 (if (string-equal rel2 "") (setq rel2 nil))
1147 (if (file-directory-p file)
1148 (let ((camefrom (current-buffer)))
1149 (set-buffer (get-buffer-create "*vc-status*"))
1150 (set (make-local-variable 'vc-parent-buffer) camefrom)
1151 (set (make-local-variable 'vc-parent-buffer-name)
1152 (concat " from " (buffer-name camefrom)))
1154 (insert "Diffs between "
1155 (or rel1 "last version checked in")
1157 (or rel2 "current workfile(s)")
1159 (set-buffer (get-buffer-create "*vc-diff*"))
1163 (function (lambda (f)
1164 (message "Looking at %s" f)
1166 (not (file-directory-p f))
1168 (vc-backend-diff f rel1 rel2)
1169 (append-to-buffer "*vc-status*" (point-min) (point-max)))
1171 (pop-to-buffer "*vc-status*")
1172 (insert "\nEnd of diffs.\n")
1173 (goto-char (point-min))
1174 (set-buffer-modified-p nil)
1176 (if (zerop (vc-backend-diff file rel1 rel2))
1177 (message "No changes to %s between %s and %s." file rel1 rel2)
1178 (pop-to-buffer "*vc-diff*"))))
1181 (defun vc-version-other-window (rev)
1182 "Visit version REV of the current buffer in another window.
1183 If the current buffer is named `F', the version is named `F.~REV~'.
1184 If `F.~REV~' already exists, it is used instead of being re-created."
1185 (interactive "sVersion to visit (default is latest version): ")
1187 (set-buffer (find-file-noselect (dired-get-filename))))
1188 (while vc-parent-buffer
1189 (pop-to-buffer vc-parent-buffer))
1190 (if (and buffer-file-name (vc-name buffer-file-name))
1191 (let* ((version (if (string-equal rev "")
1192 (vc-latest-version buffer-file-name)
1194 (filename (concat buffer-file-name ".~" version "~")))
1195 (or (file-exists-p filename)
1196 (vc-backend-checkout buffer-file-name nil version filename))
1197 (find-file-other-window filename))
1198 (vc-registration-error buffer-file-name)))
1200 ;; Header-insertion code
1203 (defun vc-insert-headers ()
1204 "Insert headers in a file for use with your version-control system.
1205 Headers desired are inserted at the start of the buffer, and are pulled from
1206 the variable `vc-header-alist'."
1209 (find-file-other-window (dired-get-filename)))
1210 (while vc-parent-buffer
1211 (pop-to-buffer vc-parent-buffer))
1215 (if (or (not (vc-check-headers))
1216 (y-or-n-p "Version headers already exist. Insert another set? "))
1218 (let* ((delims (cdr (assq major-mode vc-comment-alist)))
1219 (comment-start-vc (or (car delims) comment-start "#"))
1220 (comment-end-vc (or (car (cdr delims)) comment-end ""))
1221 (hdstrings (cdr (assoc (vc-backend (buffer-file-name)) vc-header-alist))))
1222 (mapcar (function (lambda (s)
1223 (insert comment-start-vc "\t" s "\t"
1224 comment-end-vc "\n")))
1226 (if vc-static-header-alist
1227 (mapcar (function (lambda (f)
1228 (if (string-match (car f) buffer-file-name)
1229 (insert (format (cdr f) (car hdstrings))))))
1230 vc-static-header-alist))
1234 (defun vc-clear-headers ()
1235 ;; Clear all version headers in the current buffer, i.e. reset them
1236 ;; to the nonexpanded form. Only implemented for RCS, yet.
1237 ;; Don't lose point and mark during this.
1238 (let ((context (vc-buffer-context)))
1239 (goto-char (point-min))
1240 (while (re-search-forward "\\$\\([A-Za-z]+\\): [^\\$]+\\$" nil t)
1241 (replace-match "$\\1$"))
1242 (vc-restore-buffer-context context)))
1244 ;; The VC directory major mode. Coopt Dired for this.
1245 ;; All VC commands get mapped into logical equivalents.
1247 (define-derived-mode vc-dired-mode dired-mode "Dired under VC"
1248 "The major mode used in VC directory buffers. It is derived from Dired.
1249 All Dired commands operate normally. Users currently locking listed files
1250 are listed in place of the file's owner and group.
1251 Keystrokes bound to VC commands will execute as though they had been called
1252 on a buffer attached to the file named in the current Dired buffer line."
1253 (setq vc-dired-mode t))
1255 (define-key vc-dired-mode-map "\C-xv" vc-prefix-map)
1256 (define-key vc-dired-mode-map "g" 'vc-dired-update)
1257 (define-key vc-dired-mode-map "=" 'vc-diff)
1259 (defun vc-dired-state-info (file)
1260 ;; Return the string that indicates the version control status
1261 ;; on a VC dired line.
1262 (let ((cvs-state (and (eq (vc-backend file) 'CVS)
1263 (vc-cvs-status file))))
1265 (cond ((eq cvs-state 'up-to-date) nil)
1266 ((eq cvs-state 'needs-checkout) "patch")
1267 ((eq cvs-state 'locally-modified) "modified")
1268 ((eq cvs-state 'needs-merge) "merge")
1269 ((eq cvs-state 'unresolved-conflict) "conflict")
1270 ((eq cvs-state 'locally-added) "added"))
1271 (vc-locking-user file))))
1273 (defun vc-dired-reformat-line (x)
1274 ;; Hack a directory-listing line, plugging in locking-user info in
1275 ;; place of the user and group info. Should have the beneficial
1276 ;; side-effect of shortening the listing line. Each call starts with
1277 ;; point immediately following the dired mark area on the line to be
1280 ;; Simplest possible one:
1281 ;; (insert (concat x "\t")))
1283 ;; This code, like dired, assumes UNIX -l format.
1284 (let ((pos (point)) limit perm owner date-and-file)
1286 (setq limit (point))
1290 (re-search-forward ;; owner and group
1291 "\\([drwxlts-]+ \\) *[0-9]+ \\([^ ]+\\) +[^ ]+ +[0-9]+\\( [^ 0-9]+ [0-9 ][0-9] .*\\)"
1293 (re-search-forward ;; only owner displayed
1294 "\\([drwxlts-]+ \\) *[0-9]+ \\([^ ]+\\) +[0-9]+\\( [^ 0-9]+ [0-9 ][0-9] .*\\)"
1296 (setq perm (match-string 1)
1297 owner (match-string 2)
1298 date-and-file (match-string 3)))
1299 ((re-search-forward ;; OS/2 -l format, no links, owner, group
1300 "\\([drwxlts-]+ \\) *[0-9]+\\( [^ 0-9]+ [0-9 ][0-9] .*\\)"
1302 (setq perm (match-string 1)
1303 date-and-file (match-string 2))))
1304 (if (numberp x) (setq x (or owner (number-to-string x))))
1305 (if x (setq x (concat "(" x ")")))
1306 (let ((rep (substring (concat x " ") 0 10)))
1307 (replace-match (concat perm rep date-and-file)))))
1309 (defun vc-dired-update-line (file)
1310 ;; Update the vc-dired listing line of file -- it is assumed
1311 ;; that point is already on this line. Don't use dired-do-redisplay
1312 ;; for this, because it cannot handle the way vc-dired deals with
1316 (let ((start (point)))
1319 (delete-region start (point))
1320 (insert-directory file dired-listing-switches)
1323 (delete-char (- (length file)))
1324 (insert (substring file (length (expand-file-name default-directory))))
1326 (vc-dired-reformat-line (vc-dired-state-info file)))
1328 (defun vc-dired-update (verbose)
1330 (vc-directory default-directory verbose))
1332 ;;; Note in Emacs 18 the following defun gets overridden
1333 ;;; with the symbol 'vc-directory-18. See below.
1335 (defun vc-directory (dirname verbose)
1336 "Show version-control status of the current directory and subdirectories.
1337 Normally it creates a Dired buffer that lists only the locked files
1338 in all these directories. With a prefix argument, it lists all files."
1339 (interactive "DDired under VC (directory): \nP")
1340 (setq dirname (expand-file-name dirname))
1341 ;; force a trailing slash
1342 (if (not (eq (elt dirname (1- (length dirname))) ?/))
1343 (setq dirname (concat dirname "/")))
1345 (dl (length dirname))
1346 (filelist nil) (statelist nil)
1347 (old-dir default-directory)
1349 dired-buf-mod-count)
1354 (if (vc-registered f)
1355 (let ((state (vc-dired-state-info f)))
1356 (and (or verbose state)
1357 (setq filelist (cons (substring f dl) filelist))
1358 (setq statelist (cons state statelist))))))))
1359 (save-window-excursion
1361 ;; This uses a semi-documented feature of dired; giving a switch
1362 ;; argument forces the buffer to refresh each time.
1364 (dired-internal-noselect
1365 (cons dirname (nreverse filelist))
1366 dired-listing-switches 'vc-dired-mode))
1367 (setq nonempty (not (eq 0 (length filelist))))))
1368 (switch-to-buffer dired-buf)
1369 ;; Make a few modifications to the header
1370 (setq buffer-read-only nil)
1371 (goto-char (point-min))
1372 (forward-line 1) ;; Skip header line
1373 (let ((start (point))) ;; Erase (but don't remove) the
1374 (end-of-line) ;; "wildcard" line.
1375 (delete-region start (point)))
1379 ;; Plug the version information into the individual lines
1383 (forward-char 2) ;; skip dired's mark area
1384 (vc-dired-reformat-line x)
1385 (forward-line 1))) ;; go to next line
1386 (nreverse statelist))
1387 (setq buffer-read-only t)
1388 (goto-char (point-min))
1393 (setq buffer-read-only t)
1394 (message "No files are currently %s under %s"
1395 (if verbose "registered" "locked") dirname))
1399 (defun vc-directory-18 (verbose)
1400 "Show version-control status of all files under the current directory."
1402 (let (nonempty (dir default-directory))
1404 (set-buffer (get-buffer-create "*vc-status*"))
1409 (function (lambda (f)
1410 (if (vc-registered f)
1411 (let ((user (vc-locking-user f)))
1412 (if (or user verbose)
1415 (concat user) f))))))))
1416 (setq nonempty (not (zerop (buffer-size)))))
1420 (pop-to-buffer "*vc-status*" t)
1421 (goto-char (point-min))
1422 (shrink-window-if-larger-than-buffer)))
1423 (message "No files are currently %s under %s"
1424 (if verbose "registered" "locked") default-directory))
1427 (or (boundp 'minor-mode-map-alist)
1428 (fset 'vc-directory 'vc-directory-18))
1430 ;; Named-configuration support for SCCS
1432 (defun vc-add-triple (name file rev)
1434 (find-file (expand-file-name
1436 (file-name-as-directory
1437 (expand-file-name (vc-backend-subdirectory-name file)
1438 (file-name-directory file)))))
1439 (goto-char (point-max))
1440 (insert name "\t:\t" file "\t" rev "\n")
1442 (kill-buffer (current-buffer))
1445 (defun vc-record-rename (file newname)
1450 (file-name-as-directory
1451 (expand-file-name (vc-backend-subdirectory-name file)
1452 (file-name-directory file)))))
1453 (goto-char (point-min))
1454 ;; (replace-regexp (concat ":" (regexp-quote file) "$") (concat ":" newname))
1455 (while (re-search-forward (concat ":" (regexp-quote file) "$") nil t)
1456 (replace-match (concat ":" newname) nil nil))
1458 (kill-buffer (current-buffer))
1461 (defun vc-lookup-triple (file name)
1462 ;; Return the numeric version corresponding to a named snapshot of file
1463 ;; If name is nil or a version number string it's just passed through
1464 (cond ((null name) name)
1465 ((let ((firstchar (aref name 0)))
1466 (and (>= firstchar ?0) (<= firstchar ?9)))
1470 (set-buffer (get-buffer-create "*vc-info*"))
1474 (file-name-as-directory
1475 (expand-file-name (vc-backend-subdirectory-name file)
1476 (file-name-directory file)))))
1478 (car (vc-parse-buffer
1479 (list (list (concat name "\t:\t" file "\t\\(.+\\)") 1))))
1480 (kill-buffer "*vc-info*"))))
1483 ;; Named-configuration entry points
1485 (defun vc-snapshot-precondition ()
1486 ;; Scan the tree below the current directory.
1487 ;; If any files are locked, return the name of the first such file.
1488 ;; (This means, neither snapshot creation nor retrieval is allowed.)
1489 ;; If one or more of the files are currently visited, return `visited'.
1490 ;; Otherwise, return nil.
1492 (catch 'vc-locked-example
1495 (function (lambda (f)
1496 (and (vc-registered f)
1497 (if (vc-locking-user f) (throw 'vc-locked-example f)
1498 (if (get-file-buffer f) (setq status 'visited)))))))
1502 (defun vc-create-snapshot (name)
1503 "Make a snapshot called NAME.
1504 The snapshot is made from all registered files at or below the current
1505 directory. For each file, the version level of its latest
1506 version becomes part of the named configuration."
1507 (interactive "sNew snapshot name: ")
1508 (let ((result (vc-snapshot-precondition)))
1509 (if (stringp result)
1510 (error "File %s is locked" result)
1513 (function (lambda (f) (and
1515 (vc-backend-assign-name f name)))))
1519 (defun vc-retrieve-snapshot (name)
1520 "Retrieve the snapshot called NAME.
1521 This function fails if any files are locked at or below the current directory
1522 Otherwise, all registered files are checked out (unlocked) at their version
1523 levels in the snapshot."
1524 (interactive "sSnapshot name to retrieve: ")
1525 (let ((result (vc-snapshot-precondition))
1527 (if (stringp result)
1528 (error "File %s is locked" result)
1529 (if (eq result 'visited)
1530 (setq update (yes-or-no-p "Update the affected buffers? ")))
1533 (function (lambda (f) (and
1536 (vc-backend-checkout f nil name)
1537 (if update (vc-resynch-buffer f t t)))))))
1540 ;; Miscellaneous other entry points
1543 (defun vc-print-log ()
1544 "List the change log of the current buffer in a window."
1547 (set-buffer (find-file-noselect (dired-get-filename))))
1548 (while vc-parent-buffer
1549 (pop-to-buffer vc-parent-buffer))
1550 (if (and buffer-file-name (vc-name buffer-file-name))
1551 (let ((file buffer-file-name))
1552 (vc-backend-print-log file)
1553 (pop-to-buffer (get-buffer-create "*vc*"))
1554 (setq default-directory (file-name-directory file))
1555 (while (looking-at "=*\n")
1556 (delete-char (- (match-end 0) (match-beginning 0)))
1558 (goto-char (point-min))
1559 (if (looking-at "[\b\t\n\v\f\r ]+")
1560 (delete-char (- (match-end 0) (match-beginning 0))))
1561 (shrink-window-if-larger-than-buffer)
1563 (vc-registration-error buffer-file-name)
1568 (defun vc-revert-buffer ()
1569 "Revert the current buffer's file back to the latest checked-in version.
1570 This asks for confirmation if the buffer contents are not identical
1572 If the back-end is CVS, this will give you the most recent revision of
1573 the file on the branch you are editing."
1576 (find-file-other-window (dired-get-filename)))
1577 (while vc-parent-buffer
1578 (pop-to-buffer vc-parent-buffer))
1579 (let ((file buffer-file-name)
1580 (obuf (current-buffer)) (changed (vc-diff nil t)))
1581 (if (and changed (or vc-suppress-confirm
1582 (not (yes-or-no-p "Discard changes? "))))
1584 (if (and (window-dedicated-p (selected-window))
1585 (one-window-p t 'selected-frame))
1586 (make-frame-invisible (selected-frame))
1588 (error "Revert cancelled"))
1591 (if (and (window-dedicated-p (selected-window))
1592 (one-window-p t 'selected-frame))
1593 (make-frame-invisible (selected-frame))
1595 (vc-backend-revert file)
1596 (vc-resynch-window file t t)
1601 (defun vc-cancel-version (norevert)
1602 "Get rid of most recently checked in version of this file.
1603 A prefix argument means do not revert the buffer afterwards."
1606 (find-file-other-window (dired-get-filename)))
1607 (while vc-parent-buffer
1608 (pop-to-buffer vc-parent-buffer))
1610 ((eq (vc-backend (buffer-file-name)) 'CVS)
1611 (error "Unchecking files under CVS is dangerous and not supported in VC"))
1612 ((vc-locking-user (buffer-file-name))
1613 (error "This version is locked. Use vc-revert-buffer to discard changes."))
1614 ((not (vc-latest-on-branch-p (buffer-file-name)))
1615 (error "This is not the latest version. VC cannot cancel it.")))
1616 (let ((target (vc-workfile-version (buffer-file-name))))
1617 (if (null (yes-or-no-p "Remove this version from master? "))
1619 (setq norevert (or norevert (not
1620 (yes-or-no-p "Revert buffer to most recent remaining version? "))))
1621 (vc-backend-uncheck (buffer-file-name) target)
1623 (vc-checkout (buffer-file-name) nil)
1624 ;; If norevert, lock the most recent remaining version,
1625 ;; and mark the buffer modified.
1626 (if (eq (vc-backend (buffer-file-name)) 'RCS)
1627 (progn (setq buffer-read-only nil)
1628 (vc-clear-headers)))
1629 (vc-backend-checkout (buffer-file-name) t (vc-branch-part target))
1630 (set-visited-file-name (buffer-file-name))
1631 (vc-mode-line (buffer-file-name)))
1632 (message "Version %s has been removed from the master." target)
1636 (defun vc-rename-file (old new)
1637 "Rename file OLD to NEW, and rename its master file likewise."
1638 (interactive "fVC rename file: \nFRename to: ")
1639 ;; There are several ways of renaming files under CVS 1.3, but they all
1640 ;; have serious disadvantages. See the FAQ (available from think.com in
1641 ;; pub/cvs/). I'd rather send the user an error, than do something he might
1642 ;; consider to be wrong. When the famous, long-awaited rename database is
1643 ;; implemented things might change for the better. This is unlikely to occur
1644 ;; until CVS 2.0 is released. --ceder 1994-01-23 21:27:51
1645 (if (eq (vc-backend old) 'CVS)
1646 (error "Renaming files under CVS is dangerous and not supported in VC."))
1647 (let ((oldbuf (get-file-buffer old)))
1648 (if (and oldbuf (buffer-modified-p oldbuf))
1649 (error "Please save files before moving them"))
1650 (if (get-file-buffer new)
1651 (error "Already editing new file name"))
1652 (if (file-exists-p new)
1653 (error "New file already exists"))
1654 (let ((oldmaster (vc-name old)))
1657 (if (vc-locking-user old)
1658 (error "Please check in files before moving them"))
1659 (if (or (file-symlink-p oldmaster)
1660 ;; This had FILE, I changed it to OLD. -- rms.
1661 (file-symlink-p (vc-backend-subdirectory-name old)))
1662 (error "This is not a safe thing to do in the presence of symbolic links"))
1665 (let ((backend (vc-backend old))
1666 (newdir (or (file-name-directory new) ""))
1667 (newbase (file-name-nondirectory new)))
1672 (if (eq backend (cdr s))
1673 (let* ((newmaster (format (car s) newdir newbase))
1674 (newmasterdir (file-name-directory newmaster)))
1675 (if (or (not newmasterdir)
1676 (file-directory-p newmasterdir))
1677 (throw 'found newmaster))))))
1678 vc-master-templates)
1679 (error "New file lacks a version control directory"))))))
1680 (if (or (not oldmaster) (file-exists-p old))
1681 (rename-file old new)))
1682 ; ?? Renaming a file might change its contents due to keyword expansion.
1683 ; We should really check out a new copy if the old copy was precisely equal
1684 ; to some checked in version. However, testing for this is tricky....
1688 (set-visited-file-name new)
1689 (set-buffer-modified-p nil))))
1690 ;; This had FILE, I changed it to OLD. -- rms.
1691 (vc-backend-dispatch old
1692 (vc-record-rename old new) ;SCCS
1699 (defun vc-update-change-log (&rest args)
1700 "Find change log file and add entries from recent RCS logs.
1701 The mark is left at the end of the text prepended to the change log.
1702 With prefix arg of C-u, only find log entries for the current buffer's file.
1703 With any numeric prefix arg, find log entries for all files currently visited.
1704 Otherwise, find log entries for all registered files in the default directory.
1705 From a program, any arguments are passed to the `rcs2log' script."
1707 (cond ((consp current-prefix-arg) ;C-u
1708 (list buffer-file-name))
1709 (current-prefix-arg ;Numeric argument.
1711 (buffers (buffer-list))
1714 (setq file (buffer-file-name (car buffers)))
1715 (and file (vc-backend file)
1716 (setq files (cons file files)))
1717 (setq buffers (cdr buffers)))
1720 (let ((RCS (concat default-directory "RCS")))
1721 (and (file-directory-p RCS)
1724 (if (string-match "\\(.*\\),v$" f)
1725 (substring f 0 (match-end 1))
1727 (directory-files RCS nil "...\\|^[^.]\\|^.[^.]")))))))
1728 (let ((odefault default-directory))
1729 (find-file-other-window (find-change-log))
1730 (barf-if-buffer-read-only)
1733 (goto-char (point-min))
1735 (message "Computing change log entries...")
1736 (message "Computing change log entries... %s"
1738 (eq 0 (apply 'call-process "rcs2log" nil t nil
1740 (concat (user-login-name)
1748 (if (file-name-absolute-p f)
1750 (concat odefault f)))))
1754 ;; Collect back-end-dependent stuff here
1756 (defun vc-backend-admin (file &optional rev comment)
1757 ;; Register a file into the version-control system
1758 ;; Automatically retrieves a read-only version of the file with
1759 ;; keywords expanded if vc-keep-workfiles is non-nil, otherwise
1760 ;; it deletes the workfile.
1761 (vc-file-clearprops file)
1762 (or vc-default-back-end
1763 (setq vc-default-back-end (if (vc-find-binary "rcs") 'RCS 'SCCS)))
1764 (message "Registering %s..." file)
1767 ((file-exists-p (vc-backend-subdirectory-name)) vc-default-back-end)
1768 ((file-exists-p "RCS") 'RCS)
1769 ((file-exists-p "SCCS") 'SCCS)
1770 ((file-exists-p "CVS") 'CVS)
1771 (t vc-default-back-end))))
1772 (cond ((eq backend 'SCCS)
1773 (vc-do-command nil 0 "admin" file 'MASTER ;; SCCS
1774 (and rev (concat "-r" rev))
1777 (and comment (concat "-y" comment))
1779 (car (rassq 'SCCS vc-master-templates))
1780 (or (file-name-directory file) "")
1781 (file-name-nondirectory file)))
1783 (if vc-keep-workfiles
1784 (vc-do-command nil 0 "get" file 'MASTER)))
1786 (vc-do-command nil 0 "ci" file 'MASTER ;; RCS
1787 ;; if available, use the secure registering option
1788 (and (vc-backend-release-p 'RCS "5.6.4") "-i")
1789 (concat (if vc-keep-workfiles "-u" "-r") rev)
1790 (and comment (concat "-t-" comment))
1793 (vc-do-command nil 0 "cvs" file 'WORKFILE ;; CVS
1795 (and comment (string-match "[^\t\n ]" comment)
1796 (concat "-m" comment)))
1798 (message "Registering %s...done" file)
1801 (defun vc-backend-checkout (file &optional writable rev workfile)
1802 ;; Retrieve a copy of a saved version into a workfile
1803 (let ((filename (or workfile file))
1804 (file-buffer (get-file-buffer file))
1805 (old-default-dir default-directory))
1806 (message "Checking out %s..." filename)
1808 ;; Change buffers to get local value of vc-checkin-switches.
1809 (if file-buffer (set-buffer file-buffer))
1810 ;; Adjust the default-directory so that the check-out creates
1811 ;; the file in the right place. The old value is restored below.
1812 (setq default-directory (file-name-directory filename))
1813 (vc-backend-dispatch file
1815 ;; Some SCCS implementations allow checking out directly to a
1816 ;; file using the -G option, but then some don't so use the
1817 ;; least common denominator approach and use the -p option
1819 (let ((vc-modes (logior (file-modes (vc-name file))
1820 (if writable 128 0)))
1824 (apply 'vc-do-command
1825 nil 0 "/bin/sh" file 'MASTER "-c"
1826 ;; Some shells make the "" dummy argument into $0
1827 ;; while others use the shell's name as $0 and
1828 ;; use the "" as $1. The if-statement
1829 ;; converts the latter case to the former.
1830 (format "if [ x\"$1\" = x ]; then shift; fi; \
1831 umask %o; exec >\"$1\" || exit; \
1832 shift; umask %o; exec get \"$@\""
1833 (logand 511 (lognot vc-modes))
1834 (logand 511 (lognot (default-file-modes))))
1835 "" ; dummy argument for shell's $0
1839 (concat "-r" (vc-lookup-triple file rev)))
1840 vc-checkout-switches)
1842 (and failed (file-exists-p filename) (delete-file filename))))
1843 (apply 'vc-do-command nil 0 "get" file 'MASTER ;; SCCS
1845 (and rev (concat "-r" (vc-lookup-triple file rev)))
1846 vc-checkout-switches)
1847 (vc-file-setprop file 'vc-workfile-version nil))
1849 ;; RCS doesn't let us check out into arbitrary file names directly.
1850 ;; Use `co -p' and make stdout point to the correct file.
1851 (let ((vc-modes (logior (file-modes (vc-name file))
1852 (if writable 128 0)))
1856 (apply 'vc-do-command
1857 nil 0 "/bin/sh" file 'MASTER "-c"
1858 ;; See the SCCS case, above, regarding the
1860 (format "if [ x\"$1\" = x ]; then shift; fi; \
1861 umask %o; exec >\"$1\" || exit; \
1862 shift; umask %o; exec co \"$@\""
1863 (logand 511 (lognot vc-modes))
1864 (logand 511 (lognot (default-file-modes))))
1865 "" ; dummy argument for shell's $0
1869 vc-checkout-switches)
1871 (and failed (file-exists-p filename) (delete-file filename))))
1873 ;; if we should go to the head of the trunk,
1874 ;; clear the default branch first
1875 (and rev (string= rev "")
1876 (vc-do-command nil 0 "rcs" file 'MASTER "-b"))
1877 ;; now do the checkout
1878 (apply 'vc-do-command
1879 nil 0 "co" file 'MASTER
1880 ;; If locking is not strict, force to overwrite
1881 ;; the writable workfile.
1882 (if (eq (vc-checkout-model file) 'implicit) "-f")
1884 (if rev (concat "-r" rev)
1885 ;; if no explicit revision was specified,
1886 ;; check out that of the working file
1887 (let ((workrev (vc-workfile-version file)))
1888 (if workrev (concat "-r" workrev)
1890 vc-checkout-switches)
1891 ;; determine the new workfile version
1894 (goto-char (point-min))
1896 (if (re-search-forward "^revision \\([0-9.]+\\).*\n" nil t)
1897 (buffer-substring (match-beginning 1) (match-end 1)))))
1898 (vc-file-setprop file 'vc-workfile-version new-version)
1899 ;; if necessary, adjust the default branch
1900 (and rev (not (string= rev ""))
1901 (vc-do-command nil 0 "rcs" file 'MASTER
1902 (concat "-b" (if (vc-latest-on-branch-p file)
1903 (if (vc-trunk-p new-version) nil
1904 (vc-branch-part new-version))
1907 ;; CVS is much like RCS
1911 (apply 'vc-do-command
1912 nil 0 "/bin/sh" file 'WORKFILE "-c"
1913 "exec >\"$1\" || exit; shift; exec cvs update \"$@\""
1914 "" ; dummy argument for shell's $0
1918 vc-checkout-switches)
1920 (and failed (file-exists-p filename) (delete-file filename))))
1921 ;; default for verbose checkout: clear the sticky tag
1922 ;; so that the actual update will get the head of the trunk
1923 (and rev (string= rev "")
1924 (vc-do-command nil 0 "cvs" file 'WORKFILE "update" "-A"))
1925 ;; If a revision was specified, check that out.
1927 (apply 'vc-do-command nil 0 "cvs" file 'WORKFILE
1928 (and writable (eq (vc-checkout-model file) 'manual) "-w")
1930 (and rev (not (string= rev ""))
1932 vc-checkout-switches)
1933 ;; If no revision was specified, simply make the file writable.
1935 (or (eq (vc-checkout-model file) 'manual)
1936 (zerop (logand 128 (file-modes file))))
1937 (set-file-modes file (logior 128 (file-modes file)))))
1938 (if rev (vc-file-setprop file 'vc-workfile-version nil))))
1939 (setq default-directory old-default-dir)
1942 (vc-file-clear-masterprops file)
1944 (vc-file-setprop file 'vc-locking-user (user-login-name)))
1945 (vc-file-setprop file
1946 'vc-checkout-time (nth 5 (file-attributes file)))))
1947 (message "Checking out %s...done" filename))))
1949 (defun vc-backend-logentry-check (file)
1950 (vc-backend-dispatch file
1951 (if (>= (buffer-size) 512) ;; SCCS
1955 "Log must be less than 512 characters; point is now at pos 512")))
1960 (defun vc-backend-checkin (file rev comment)
1961 ;; Register changes to FILE as level REV with explanatory COMMENT.
1962 ;; Automatically retrieves a read-only version of the file with
1963 ;; keywords expanded if vc-keep-workfiles is non-nil, otherwise
1964 ;; it deletes the workfile.
1965 ;; Adaption for RCS branch support: if this is an explicit checkin,
1966 ;; or if the checkin creates a new branch, set the master file branch
1968 (message "Checking in %s..." file)
1969 ;; "This log message intentionally left almost blank".
1970 ;; RCS 5.7 gripes about white-space-only comments too.
1971 (or (and comment (string-match "[^\t\n ]" comment))
1972 (setq comment "*** empty log message ***"))
1974 ;; Change buffers to get local value of vc-checkin-switches.
1975 (set-buffer (or (get-file-buffer file) (current-buffer)))
1976 ;; Clear the master-properties. Do that here, not at the
1977 ;; end, because if the check-in fails we want them to get
1978 ;; re-computed before the next try.
1979 (vc-file-clear-masterprops file)
1980 (vc-backend-dispatch file
1983 (apply 'vc-do-command nil 0 "delta" file 'MASTER
1984 (if rev (concat "-r" rev))
1985 (concat "-y" comment)
1986 vc-checkin-switches)
1987 (vc-file-setprop file 'vc-locking-user 'none)
1988 (vc-file-setprop file 'vc-workfile-version nil)
1989 (if vc-keep-workfiles
1990 (vc-do-command nil 0 "get" file 'MASTER))
1993 (let ((old-version (vc-workfile-version file)) new-version)
1994 (apply 'vc-do-command nil 0 "ci" file 'MASTER
1995 ;; if available, use the secure check-in option
1996 (and (vc-backend-release-p 'RCS "5.6.4") "-j")
1997 (concat (if vc-keep-workfiles "-u" "-r") rev)
1998 (concat "-m" comment)
1999 vc-checkin-switches)
2000 (vc-file-setprop file 'vc-locking-user 'none)
2001 (vc-file-setprop file 'vc-workfile-version nil)
2003 ;; determine the new workfile version
2005 (goto-char (point-min))
2006 (if (or (re-search-forward
2007 "new revision: \\([0-9.]+\\);" nil t)
2009 "reverting to previous revision \\([0-9.]+\\)" nil t))
2010 (progn (setq new-version (buffer-substring (match-beginning 1)
2012 (vc-file-setprop file 'vc-workfile-version new-version)))
2014 ;; if we got to a different branch, adjust the default
2015 ;; branch accordingly
2017 ((and old-version new-version
2018 (not (string= (vc-branch-part old-version)
2019 (vc-branch-part new-version))))
2020 (vc-do-command nil 0 "rcs" file 'MASTER
2021 (if (vc-trunk-p new-version) "-b"
2022 (concat "-b" (vc-branch-part new-version))))
2023 ;; If this is an old RCS release, we might have
2024 ;; to remove a remaining lock.
2025 (if (not (vc-backend-release-p 'RCS "5.6.2"))
2026 ;; exit status of 1 is also accepted.
2027 ;; It means that the lock was removed before.
2028 (vc-do-command nil 1 "rcs" file 'MASTER
2029 (concat "-u" old-version))))))
2032 ;; explicit check-in to the trunk requires a
2033 ;; double check-in (first unexplicit) (CVS-1.3)
2036 (if (and rev (vc-trunk-p rev))
2037 (apply 'vc-do-command nil 0 "cvs" file 'WORKFILE
2038 "ci" "-m" "intermediate"
2039 vc-checkin-switches))
2040 (apply 'vc-do-command nil 0 "cvs" file 'WORKFILE
2041 "ci" (if rev (concat "-r" rev))
2042 (concat "-m" comment)
2043 vc-checkin-switches))
2044 (error (if (eq (vc-cvs-status file) 'needs-merge)
2045 ;; The CVS output will be on top of this message.
2046 (error "Type C-x 0 C-x C-q to merge in changes.")
2047 (error "Check in FAILED."))))
2048 ;; determine and store the new workfile version
2050 (goto-char (point-min))
2051 (if (re-search-forward
2052 "^\\(new\\|initial\\) revision: \\([0-9.]+\\)" nil t)
2053 (vc-file-setprop file 'vc-workfile-version
2054 (buffer-substring (match-beginning 2)
2056 (vc-file-setprop file 'vc-workfile-version nil))
2057 ;; if this was an explicit check-in, remove the sticky tag
2059 (vc-do-command nil 0 "cvs" file 'WORKFILE "update" "-A"))
2060 (vc-file-setprop file 'vc-locking-user 'none)
2061 (vc-file-setprop file 'vc-checkout-time
2062 (nth 5 (file-attributes file))))))
2063 (message "Checking in %s...done" file))
2065 (defun vc-backend-revert (file)
2066 ;; Revert file to latest checked-in version.
2067 ;; (for RCS, to workfile version)
2068 (message "Reverting %s..." file)
2069 (vc-file-clear-masterprops file)
2070 (vc-backend-dispatch
2074 (vc-do-command nil 0 "unget" file 'MASTER nil)
2075 (vc-do-command nil 0 "get" file 'MASTER nil))
2077 (vc-do-command nil 0 "co" file 'MASTER
2078 "-f" (concat "-u" (vc-workfile-version file)))
2082 (vc-do-command nil 0 "cvs" file 'WORKFILE "update")))
2083 (vc-file-setprop file 'vc-locking-user 'none)
2084 (vc-file-setprop file 'vc-checkout-time (nth 5 (file-attributes file)))
2085 (message "Reverting %s...done" file)
2088 (defun vc-backend-steal (file &optional rev)
2089 ;; Steal the lock on the current workfile. Needs RCS 5.6.2 or later for -M.
2090 (message "Stealing lock on %s..." file)
2091 (vc-backend-dispatch file
2093 (vc-do-command nil 0 "unget" file 'MASTER "-n" (if rev (concat "-r" rev)))
2094 (vc-do-command nil 0 "get" file 'MASTER "-g" (if rev (concat "-r" rev)))
2096 (vc-do-command nil 0 "rcs" file 'MASTER ;RCS
2097 "-M" (concat "-u" rev) (concat "-l" rev))
2098 (error "You cannot steal a CVS lock; there are no CVS locks to steal.") ;CVS
2100 (vc-file-setprop file 'vc-locking-user (user-login-name))
2101 (message "Stealing lock on %s...done" file)
2104 (defun vc-backend-uncheck (file target)
2105 ;; Undo the latest checkin.
2106 (message "Removing last change from %s..." file)
2107 (vc-backend-dispatch file
2108 (vc-do-command nil 0 "rmdel" file 'MASTER (concat "-r" target))
2109 (vc-do-command nil 0 "rcs" file 'MASTER (concat "-o" target))
2110 nil ;; this is never reached under CVS
2112 (message "Removing last change from %s...done" file)
2115 (defun vc-backend-print-log (file)
2116 ;; Get change log associated with FILE.
2117 (vc-backend-dispatch
2119 (vc-do-command nil 0 "prs" file 'MASTER)
2120 (vc-do-command nil 0 "rlog" file 'MASTER)
2121 (vc-do-command nil 0 "cvs" file 'WORKFILE "rlog")))
2123 (defun vc-backend-assign-name (file name)
2124 ;; Assign to a FILE's latest version a given NAME.
2125 (vc-backend-dispatch file
2126 (vc-add-triple name file (vc-latest-version file)) ;; SCCS
2127 (vc-do-command nil 0 "rcs" file 'MASTER (concat "-n" name ":")) ;; RCS
2128 (vc-do-command nil 0 "cvs" file 'WORKFILE "tag" name) ;; CVS
2132 (defun vc-backend-diff (file &optional oldvers newvers cmp)
2133 ;; Get a difference report between two versions of FILE.
2134 ;; Get only a brief comparison report if CMP, a difference report otherwise.
2135 (let ((backend (vc-backend file)))
2138 (setq oldvers (vc-lookup-triple file oldvers))
2139 (setq newvers (vc-lookup-triple file newvers)))
2141 (if (not oldvers) (setq oldvers (vc-workfile-version file)))))
2142 ;; SCCS and RCS shares a lot of code.
2144 ((or (eq backend 'SCCS) (eq backend 'RCS))
2145 (let* ((command (if (eq backend 'SCCS)
2148 (mode (if (eq backend 'RCS) 'WORKFILE 'MASTER))
2149 (options (append (list (and cmp "--brief")
2151 (and oldvers (concat "-r" oldvers))
2152 (and newvers (concat "-r" newvers)))
2154 (if (listp diff-switches)
2156 (list diff-switches)))))
2157 (status (apply 'vc-do-command "*vc-diff*" 2
2158 command file mode options)))
2159 ;; Some RCS versions don't understand "--brief"; work around this.
2161 (apply 'vc-do-command "*vc-diff*" 1 command file 'WORKFILE
2162 (if cmp (cdr options) options))
2164 ;; CVS is different.
2166 (if (string= (vc-workfile-version file) "0") ;CVS
2167 ;; This file is added but not yet committed; there is no master file.
2168 (if (or oldvers newvers)
2169 (error "No revisions of %s exist" file)
2170 (if cmp 1 ;; file is added but not committed,
2171 ;; we regard this as "changed".
2172 ;; diff it against /dev/null.
2173 (apply 'vc-do-command
2174 "*vc-diff*" 1 "diff" file 'WORKFILE
2175 (append (if (listp diff-switches)
2177 (list diff-switches)) '("/dev/null")))))
2178 ;; cmp is not yet implemented -- we always do a full diff.
2179 (apply 'vc-do-command
2180 "*vc-diff*" 1 "cvs" file 'WORKFILE "diff"
2181 (and oldvers (concat "-r" oldvers))
2182 (and newvers (concat "-r" newvers))
2183 (if (listp diff-switches)
2185 (list diff-switches)))))
2187 (vc-registration-error file)))))
2189 (defun vc-backend-merge-news (file)
2190 ;; Merge in any new changes made to FILE.
2191 (message "Merging changes into %s..." file)
2193 (vc-backend-dispatch
2195 (error "vc-backend-merge-news not meaningful for SCCS files") ;SCCS
2196 (error "vc-backend-merge-news not meaningful for RCS files") ;RCS
2197 (save-excursion ; CVS
2198 (vc-file-clear-masterprops file)
2199 (vc-file-setprop file 'vc-workfile-version nil)
2200 (vc-file-setprop file 'vc-locking-user nil)
2201 (vc-do-command nil 0 "cvs" file 'WORKFILE "update")
2202 ;; CVS doesn't return an error code if conflicts are detected.
2203 ;; Since we want to warn the user about it (and possibly start
2204 ;; emerge later), scan the output and see if this occurred.
2205 (set-buffer (get-buffer "*vc*"))
2206 (goto-char (point-min))
2207 (if (re-search-forward "^cvs update: conflicts found in .*" nil t)
2208 1 ;; error code for caller
2209 0 ;; no conflict detected
2211 (message "Merging changes into %s...done" file)))
2213 (defun vc-check-headers ()
2214 "Check if the current file has any headers in it."
2217 (goto-char (point-min))
2218 (vc-backend-dispatch buffer-file-name
2219 (re-search-forward "%[MIRLBSDHTEGUYFPQCZWA]%" nil t) ;; SCCS
2220 (re-search-forward "\\$[A-Za-z\300-\326\330-\366\370-\377]+\\(: [\t -#%-\176\240-\377]*\\)?\\$" nil t) ;; RCS
2221 'RCS ;; CVS works like RCS in this regard.
2225 ;; Back-end-dependent stuff ends here.
2227 ;; Set up key bindings for use while editing log messages
2229 (defun vc-log-mode ()
2230 "Minor mode for driving version-control tools.
2231 These bindings are added to the global keymap when you enter this mode:
2232 \\[vc-next-action] perform next logical version-control operation on current file
2233 \\[vc-register] register current file
2234 \\[vc-toggle-read-only] like next-action, but won't register files
2235 \\[vc-insert-headers] insert version-control headers in current file
2236 \\[vc-print-log] display change history of current file
2237 \\[vc-revert-buffer] revert buffer to latest version
2238 \\[vc-cancel-version] undo latest checkin
2239 \\[vc-diff] show diffs between file versions
2240 \\[vc-version-other-window] visit old version in another window
2241 \\[vc-directory] show all files locked by any user in or below .
2242 \\[vc-update-change-log] add change log entry from recent checkins
2244 While you are entering a change log message for a version, the following
2245 additional bindings will be in effect.
2247 \\[vc-finish-logentry] proceed with check in, ending log message entry
2249 Whenever you do a checkin, your log comment is added to a ring of
2250 saved comments. These can be recalled as follows:
2252 \\[vc-next-comment] replace region with next message in comment ring
2253 \\[vc-previous-comment] replace region with previous message in comment ring
2254 \\[vc-comment-search-reverse] search backward for regexp in the comment ring
2255 \\[vc-comment-search-forward] search backward for regexp in the comment ring
2257 Entry to the change-log submode calls the value of text-mode-hook, then
2258 the value of vc-log-mode-hook.
2260 Global user options:
2261 vc-initial-comment If non-nil, require user to enter a change
2262 comment upon first checkin of the file.
2264 vc-keep-workfiles Non-nil value prevents workfiles from being
2265 deleted when changes are checked in
2267 vc-suppress-confirm Suppresses some confirmation prompts,
2268 notably for reversions.
2270 vc-header-alist Which keywords to insert when adding headers
2271 with \\[vc-insert-headers]. Defaults to
2272 '(\"\%\W\%\") under SCCS, '(\"\$Id\$\") under
2275 vc-static-header-alist By default, version headers inserted in C files
2276 get stuffed in a static string area so that
2277 ident(RCS/CVS) or what(SCCS) can see them in
2278 the compiled object code. You can override
2279 this by setting this variable to nil, or change
2280 the header template by changing it.
2282 vc-command-messages if non-nil, display run messages from the
2283 actual version-control utilities (this is
2284 intended primarily for people hacking vc
2288 (set-syntax-table text-mode-syntax-table)
2289 (use-local-map vc-log-entry-mode)
2290 (setq local-abbrev-table text-mode-abbrev-table)
2291 (setq major-mode 'vc-log-mode)
2292 (setq mode-name "VC-Log")
2293 (make-local-variable 'vc-log-file)
2294 (make-local-variable 'vc-log-version)
2295 (make-local-variable 'vc-comment-ring-index)
2296 (set-buffer-modified-p nil)
2297 (setq buffer-file-name nil)
2298 (run-hooks 'text-mode-hook 'vc-log-mode-hook)
2301 ;; Initialization code, to be done just once at load-time
2302 (if vc-log-entry-mode
2304 (setq vc-log-entry-mode (make-sparse-keymap))
2305 (define-key vc-log-entry-mode "\M-n" 'vc-next-comment)
2306 (define-key vc-log-entry-mode "\M-p" 'vc-previous-comment)
2307 (define-key vc-log-entry-mode "\M-r" 'vc-comment-search-reverse)
2308 (define-key vc-log-entry-mode "\M-s" 'vc-comment-search-forward)
2309 (define-key vc-log-entry-mode "\C-c\C-c" 'vc-finish-logentry)
2312 ;;; These things should probably be generally available
2314 (defun vc-file-tree-walk (dirname func &rest args)
2315 "Walk recursively through DIRNAME.
2316 Invoke FUNC f ARGS on each non-directory file f underneath it."
2317 (vc-file-tree-walk-internal (expand-file-name dirname) func args)
2318 (message "Traversing directory %s...done" dirname))
2320 (defun vc-file-tree-walk-internal (file func args)
2321 (if (not (file-directory-p file))
2322 (apply func file args)
2323 (message "Traversing directory %s..." (abbreviate-file-name file))
2324 (let ((dir (file-name-as-directory file)))
2328 (string-equal f ".")
2329 (string-equal f "..")
2330 (member f vc-directory-exclusion-list)
2331 (let ((dirf (concat dir f)))
2333 (file-symlink-p dirf) ;; Avoid possible loops
2334 (vc-file-tree-walk-internal dirf func args))))))
2335 (directory-files dir)))))
2339 ;;; DEVELOPER'S NOTES ON CONCURRENCY PROBLEMS IN THIS CODE
2341 ;;; These may be useful to anyone who has to debug or extend the package.
2342 ;;; (Note that this information corresponds to versions 5.x. Some of it
2343 ;;; might have been invalidated by the additions to support branching
2344 ;;; and RCS keyword lookup. AS, 1995/03/24)
2346 ;;; A fundamental problem in VC is that there are time windows between
2347 ;;; vc-next-action's computations of the file's version-control state and
2348 ;;; the actions that change it. This is a window open to lossage in a
2349 ;;; multi-user environment; someone else could nip in and change the state
2350 ;;; of the master during it.
2352 ;;; The performance problem is that rlog/prs calls are very expensive; we want
2353 ;;; to avoid them as much as possible.
2357 ;;; The performance problem, it turns out, simplifies in practice to the
2358 ;;; problem of making vc-locking-user fast. The two other functions that call
2359 ;;; prs/rlog will not be so commonly used that the slowdown is a problem; one
2360 ;;; makes snapshots, the other deletes the calling user's last change in the
2363 ;;; The race condition implies that we have to either (a) lock the master
2364 ;;; during the entire execution of vc-next-action, or (b) detect and
2365 ;;; recover from errors resulting from dispatch on an out-of-date state.
2367 ;;; Alternative (a) appears to be unfeasible. The problem is that we can't
2368 ;;; guarantee that the lock will ever be removed. Suppose a user starts a
2369 ;;; checkin, the change message buffer pops up, and the user, having wandered
2370 ;;; off to do something else, simply forgets about it?
2372 ;;; Alternative (b), on the other hand, works well with a cheap way to speed up
2373 ;;; vc-locking-user. Usually, if a file is registered, we can read its locked/
2374 ;;; unlocked state and its current owner from its permissions.
2376 ;;; This shortcut will fail if someone has manually changed the workfile's
2377 ;;; permissions; also if developers are munging the workfile in several
2378 ;;; directories, with symlinks to a master (in this latter case, the
2379 ;;; permissions shortcut will fail to detect a lock asserted from another
2382 ;;; Note that these cases correspond exactly to the errors which could happen
2383 ;;; because of a competing checkin/checkout race in between two instances of
2386 ;;; For VC's purposes, a workfile/master pair may have the following states:
2388 ;;; A. Unregistered. There is a workfile, there is no master.
2390 ;;; B. Registered and not locked by anyone.
2392 ;;; C. Locked by calling user and unchanged.
2394 ;;; D. Locked by the calling user and changed.
2396 ;;; E. Locked by someone other than the calling user.
2398 ;;; This makes for 25 states and 20 error conditions. Here's the matrix:
2400 ;;; VC's idea of state
2402 ;;; V Actual state RCS action SCCS action Effect
2404 ;;; A . 1 2 3 4 ci -u -t- admin -fb -i<file> initial admin
2405 ;;; B 5 . 6 7 8 co -l get -e checkout
2406 ;;; C 9 10 . 11 12 co -u unget; get revert
2407 ;;; D 13 14 15 . 16 ci -u -m<comment> delta -y<comment>; get checkin
2408 ;;; E 17 18 19 20 . rcs -u -M -l unget -n ; get -g steal lock
2410 ;;; All commands take the master file name as a last argument (not shown).
2412 ;;; In the discussion below, a "self-race" is a pathological situation in
2413 ;;; which VC operations are being attempted simultaneously by two or more
2414 ;;; Emacsen running under the same username.
2416 ;;; The vc-next-action code has the following windows:
2419 ;;; Between the check for existence of a master file and the call to
2420 ;;; admin/checkin in vc-buffer-admin (apparent state A). This window may
2421 ;;; never close if the initial-comment feature is on.
2424 ;;; Between the call to vc-workfile-unchanged-p in and the immediately
2425 ;;; following revert (apparent state C).
2428 ;;; Between the call to vc-workfile-unchanged-p in and the following
2429 ;;; checkin (apparent state D). This window may never close.
2432 ;;; Between the unlock and the immediately following checkout during a
2433 ;;; revert operation (apparent state C). Included in window Q.
2436 ;;; Between vc-locking-user and the following checkout (apparent state B).
2439 ;;; Between vc-locking-user and the following revert (apparent state C).
2440 ;;; Includes windows Q and S.
2443 ;;; Between vc-locking-user and the following checkin (apparent state
2444 ;;; D). This window may never be closed if the user fails to complete the
2445 ;;; checkin message. Includes window R.
2448 ;;; Between vc-locking-user and the following steal-lock (apparent
2449 ;;; state E). This window may never close if the user fails to complete
2450 ;;; the steal-lock message. Includes window X.
2453 ;;; Between the unlock and the immediately following re-lock during a
2454 ;;; steal-lock operation (apparent state E). This window may never cloce
2455 ;;; if the user fails to complete the steal-lock message.
2459 ;;; Apparent state A ---
2461 ;;; 1. File looked unregistered but is actually registered and not locked.
2463 ;;; Potential cause: someone else's admin during window P, with
2464 ;;; caller's admin happening before their checkout.
2466 ;;; RCS: Prior to version 5.6.4, ci fails with message
2467 ;;; "no lock set by <user>". From 5.6.4 onwards, VC uses the new
2468 ;;; ci -i option and the message is "<file>,v: already exists".
2469 ;;; SCCS: admin will fail with error (ad19).
2471 ;;; We can let these errors be passed up to the user.
2473 ;;; 2. File looked unregistered but is actually locked by caller, unchanged.
2475 ;;; Potential cause: self-race during window P.
2477 ;;; RCS: Prior to version 5.6.4, reverts the file to the last saved
2478 ;;; version and unlocks it. From 5.6.4 onwards, VC uses the new
2479 ;;; ci -i option, failing with message "<file>,v: already exists".
2480 ;;; SCCS: will fail with error (ad19).
2482 ;;; Either of these consequences is acceptable.
2484 ;;; 3. File looked unregistered but is actually locked by caller, changed.
2486 ;;; Potential cause: self-race during window P.
2488 ;;; RCS: Prior to version 5.6.4, VC registers the caller's workfile as
2489 ;;; a delta with a null change comment (the -t- switch will be
2490 ;;; ignored). From 5.6.4 onwards, VC uses the new ci -i option,
2491 ;;; failing with message "<file>,v: already exists".
2492 ;;; SCCS: will fail with error (ad19).
2494 ;;; 4. File looked unregistered but is locked by someone else.
2496 ;;; Potential cause: someone else's admin during window P, with
2497 ;;; caller's admin happening *after* their checkout.
2499 ;;; RCS: Prior to version 5.6.4, ci fails with a
2500 ;;; "no lock set by <user>" message. From 5.6.4 onwards,
2501 ;;; VC uses the new ci -i option, failing with message
2502 ;;; "<file>,v: already exists".
2503 ;;; SCCS: will fail with error (ad19).
2505 ;;; We can let these errors be passed up to the user.
2507 ;;; Apparent state B ---
2509 ;;; 5. File looked registered and not locked, but is actually unregistered.
2511 ;;; Potential cause: master file got nuked during window P.
2513 ;;; RCS: will fail with "RCS/<file>: No such file or directory"
2514 ;;; SCCS: will fail with error ut4.
2516 ;;; We can let these errors be passed up to the user.
2518 ;;; 6. File looked registered and not locked, but is actually locked by the
2519 ;;; calling user and unchanged.
2521 ;;; Potential cause: self-race during window T.
2523 ;;; RCS: in the same directory as the previous workfile, co -l will fail
2524 ;;; with "co error: writable foo exists; checkout aborted". In any other
2525 ;;; directory, checkout will succeed.
2526 ;;; SCCS: will fail with ge17.
2528 ;;; Either of these consequences is acceptable.
2530 ;;; 7. File looked registered and not locked, but is actually locked by the
2531 ;;; calling user and changed.
2535 ;;; 8. File looked registered and not locked, but is actually locked by another
2538 ;;; Potential cause: someone else checks it out during window T.
2540 ;;; RCS: co error: revision 1.3 already locked by <user>
2541 ;;; SCCS: fails with ge4 (in directory) or ut7 (outside it).
2543 ;;; We can let these errors be passed up to the user.
2545 ;;; Apparent state C ---
2547 ;;; 9. File looks locked by calling user and unchanged, but is unregistered.
2551 ;;; 10. File looks locked by calling user and unchanged, but is actually not
2554 ;;; Potential cause: a self-race in window U, or by the revert's
2555 ;;; landing during window X of some other user's steal-lock or window S
2556 ;;; of another user's revert.
2558 ;;; RCS: succeeds, refreshing the file from the identical version in
2560 ;;; SCCS: fails with error ut4 (p file nonexistent).
2562 ;;; Either of these consequences is acceptable.
2564 ;;; 11. File is locked by calling user. It looks unchanged, but is actually
2567 ;;; Potential cause: the file would have to be touched by a self-race
2568 ;;; during window Q.
2570 ;;; The revert will succeed, removing whatever changes came with
2571 ;;; the touch. It is theoretically possible that work could be lost.
2573 ;;; 12. File looks like it's locked by the calling user and unchanged, but
2574 ;;; it's actually locked by someone else.
2576 ;;; Potential cause: a steal-lock in window V.
2578 ;;; RCS: co error: revision <rev> locked by <user>; use co -r or rcs -u
2579 ;;; SCCS: fails with error un2
2581 ;;; We can pass these errors up to the user.
2583 ;;; Apparent state D ---
2585 ;;; 13. File looks like it's locked by the calling user and changed, but it's
2586 ;;; actually unregistered.
2588 ;;; Potential cause: master file got nuked during window P.
2590 ;;; RCS: Prior to version 5.6.4, checks in the user's version as an
2591 ;;; initial delta. From 5.6.4 onwards, VC uses the new ci -j
2592 ;;; option, failing with message "no such file or directory".
2593 ;;; SCCS: will fail with error ut4.
2595 ;;; This case is kind of nasty. Under RCS prior to version 5.6.4,
2596 ;;; VC may fail to detect the loss of previous version information.
2598 ;;; 14. File looks like it's locked by the calling user and changed, but it's
2599 ;;; actually unlocked.
2601 ;;; Potential cause: self-race in window V, or the checkin happening
2602 ;;; during the window X of someone else's steal-lock or window S of
2603 ;;; someone else's revert.
2605 ;;; RCS: ci will fail with "no lock set by <user>".
2606 ;;; SCCS: delta will fail with error ut4.
2608 ;;; 15. File looks like it's locked by the calling user and changed, but it's
2609 ;;; actually locked by the calling user and unchanged.
2611 ;;; Potential cause: another self-race --- a whole checkin/checkout
2612 ;;; sequence by the calling user would have to land in window R.
2614 ;;; SCCS: checks in a redundant delta and leaves the file unlocked as usual.
2615 ;;; RCS: reverts to the file state as of the second user's checkin, leaving
2616 ;;; the file unlocked.
2618 ;;; It is theoretically possible that work could be lost under RCS.
2620 ;;; 16. File looks like it's locked by the calling user and changed, but it's
2621 ;;; actually locked by a different user.
2623 ;;; RCS: ci error: no lock set by <user>
2624 ;;; SCCS: unget will fail with error un2
2626 ;;; We can pass these errors up to the user.
2628 ;;; Apparent state E ---
2630 ;;; 17. File looks like it's locked by some other user, but it's actually
2635 ;;; 18. File looks like it's locked by some other user, but it's actually
2638 ;;; Potential cause: someone released a lock during window W.
2640 ;;; RCS: The calling user will get the lock on the file.
2641 ;;; SCCS: unget -n will fail with cm4.
2643 ;;; Either of these consequences will be OK.
2645 ;;; 19. File looks like it's locked by some other user, but it's actually
2646 ;;; locked by the calling user and unchanged.
2648 ;;; Potential cause: the other user relinquishing a lock followed by
2649 ;;; a self-race, both in window W.
2651 ;;; Under both RCS and SCCS, both unlock and lock will succeed, making
2652 ;;; the sequence a no-op.
2654 ;;; 20. File looks like it's locked by some other user, but it's actually
2655 ;;; locked by the calling user and changed.
2661 ;;; In order of decreasing severity:
2663 ;;; Cases 11 and 15 are the only ones that potentially lose work.
2664 ;;; They would require a self-race for this to happen.
2666 ;;; Case 13 in RCS loses information about previous deltas, retaining
2667 ;;; only the information in the current workfile. This can only happen
2668 ;;; if the master file gets nuked in window P.
2670 ;;; Case 3 in RCS and case 15 under SCCS insert a redundant delta with
2671 ;;; no change comment in the master. This would require a self-race in
2672 ;;; window P or R respectively.
2674 ;;; Cases 2, 10, 19 and 20 do extra work, but make no changes.
2676 ;;; Unfortunately, it appears to me that no recovery is possible in these
2677 ;;; cases. They don't yield error messages, so there's no way to tell that
2678 ;;; a race condition has occurred.
2680 ;;; All other cases don't change either the workfile or the master, and
2681 ;;; trigger command errors which the user will see.
2683 ;;; Thus, there is no explicit recovery code.