Improve the explanation of version control to include concepts
[emacs.git] / lisp / ediff-vers.el
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1 ;;; ediff-vers.el --- version control interface to Ediff
3 ;; Copyright (C) 1995, 1996, 1997, 2001, 2002, 2003, 2004,
4 ;; 2005, 2006, 2007 Free Software Foundation, Inc.
6 ;; Author: Michael Kifer <kifer@cs.stonybrook.edu>
8 ;; This file is part of GNU Emacs.
10 ;; GNU Emacs is free software; you can redistribute it and/or modify
11 ;; it under the terms of the GNU General Public License as published by
12 ;; the Free Software Foundation; either version 2, or (at your option)
13 ;; any later version.
15 ;; GNU Emacs is distributed in the hope that it will be useful,
16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 ;; GNU General Public License for more details.
20 ;; You should have received a copy of the GNU General Public License
21 ;; along with GNU Emacs; see the file COPYING. If not, write to the
22 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
23 ;; Boston, MA 02110-1301, USA.
25 ;;; Commentary:
27 ;;; Code:
29 ;; Compiler pacifier
30 (defvar rcs-default-co-switches)
31 (defvar sc-mode)
32 (defvar cvs-shell)
33 (defvar cvs-program)
34 (defvar cvs-cookie-handle)
35 (defvar ediff-temp-file-prefix)
37 (and noninteractive
38 (eval-when-compile
39 (let ((load-path (cons (expand-file-name ".") load-path)))
40 (load "pcl-cvs" 'noerror)
41 (load "rcs" 'noerror)
42 ;; On 8+3 MS-DOS filesystems, generic-x.el is loaded
43 ;; instead of (the missing) generic-sc.el. Since the
44 ;; version of Emacs which supports MS-DOS doesn't have
45 ;; generic-sc, we simply avoid loading it.
46 (or (and (fboundp 'msdos-long-file-names)
47 (not (msdos-long-file-names)))
48 (load "generic-sc" 'noerror))
49 ;; (load "vc" 'noerror) ; this sometimes causes compiler error
50 (or (featurep 'ediff-init)
51 (load "ediff-init.el" nil nil 'nosuffix))
52 )))
53 ;; end pacifier
55 (defcustom ediff-keep-tmp-versions nil
56 "*If t, do not delete temporary previous versions for the files on which
57 comparison or merge operations are being performed."
58 :type 'boolean
59 :group 'ediff-vers
62 ;; VC.el support
64 (defun ediff-vc-latest-version (file)
65 "Return the version level of the latest version of FILE in repository."
66 (if (fboundp 'vc-latest-version)
67 (vc-latest-version file)
68 (or (vc-file-getprop file 'vc-latest-version)
69 (cond ((vc-backend file)
70 (vc-call state file)
71 (vc-file-getprop file 'vc-latest-version))
72 (t (error "File %s is not under version control" file))))
76 (defun ediff-vc-internal (rev1 rev2 &optional startup-hooks)
77 ;; Run Ediff on versions of the current buffer.
78 ;; If REV1 is "", use the latest version of the current buffer's file.
79 ;; If REV2 is "" then compare current buffer with REV1.
80 ;; If the current buffer is named `F', the version is named `F.~REV~'.
81 ;; If `F.~REV~' already exists, it is used instead of being re-created.
82 (let (file1 file2 rev1buf rev2buf)
83 (if (string= rev1 "")
84 (setq rev1 (ediff-vc-latest-version (buffer-file-name))))
85 (save-window-excursion
86 (save-excursion
87 (vc-version-other-window rev1)
88 (setq rev1buf (current-buffer)
89 file1 (buffer-file-name)))
90 (save-excursion
91 (or (string= rev2 "") ; use current buffer
92 (vc-version-other-window rev2))
93 (setq rev2buf (current-buffer)
94 file2 (buffer-file-name)))
95 (setq startup-hooks
96 (cons `(lambda ()
97 (ediff-delete-version-file ,file1)
98 (or ,(string= rev2 "") (ediff-delete-version-file ,file2)))
99 startup-hooks)))
100 (ediff-buffers
101 rev1buf rev2buf
102 startup-hooks
103 'ediff-revision)))
105 ;; RCS.el support
106 (defun rcs-ediff-view-revision (&optional rev)
107 ;; View previous RCS revision of current file.
108 ;; With prefix argument, prompts for a revision name.
109 (interactive (list (if current-prefix-arg
110 (read-string "Revision: "))))
111 (let* ((filename (buffer-file-name (current-buffer)))
112 (switches (append '("-p")
113 (if rev (list (concat "-r" rev)) nil)))
114 (buff (concat (file-name-nondirectory filename) ".~" rev "~")))
115 (message "Working ...")
116 (setq filename (expand-file-name filename))
117 (with-output-to-temp-buffer buff
118 (ediff-with-current-buffer standard-output
119 (fundamental-mode))
120 (let ((output-buffer (ediff-rcs-get-output-buffer filename buff)))
121 (delete-windows-on output-buffer)
122 (save-excursion
123 (set-buffer output-buffer)
124 (apply 'call-process "co" nil t nil
125 ;; -q: quiet (no diagnostics)
126 (append switches rcs-default-co-switches
127 (list "-q" filename)))))
128 (message "")
129 buff)))
131 (defun ediff-rcs-get-output-buffer (file name)
132 ;; Get a buffer for RCS output for FILE, make it writable and clean it up.
133 ;; Optional NAME is name to use instead of `*RCS-output*'.
134 ;; This is a modified version from rcs.el v1.1. I use it here to make
135 ;; Ediff immune to changes in rcs.el
136 (let* ((default-major-mode 'fundamental-mode) ; no frills!
137 (buf (get-buffer-create name)))
138 (save-excursion
139 (set-buffer buf)
140 (setq buffer-read-only nil
141 default-directory (file-name-directory (expand-file-name file)))
142 (erase-buffer))
143 buf))
145 (defun ediff-rcs-internal (rev1 rev2 &optional startup-hooks)
146 ;; Run Ediff on versions of the current buffer.
147 ;; If REV2 is "" then use current buffer.
148 (let (rev2buf rev1buf)
149 (save-window-excursion
150 (setq rev2buf (if (string= rev2 "")
151 (current-buffer)
152 (rcs-ediff-view-revision rev2))
153 rev1buf (rcs-ediff-view-revision rev1)))
155 ;; rcs.el doesn't create temp version files, so we don't have to delete
156 ;; anything in startup hooks to ediff-buffers
157 (ediff-buffers rev1buf rev2buf startup-hooks 'ediff-revision)
161 ;; GENERIC-SC.el support
163 (defun generic-sc-get-latest-rev ()
164 (cond ((eq sc-mode 'CCASE)
165 (eval "main/LATEST"))
166 (t (eval ""))))
168 (defun ediff-generic-sc-internal (rev1 rev2 &optional startup-hooks)
169 ;; Run Ediff on versions of the current buffer.
170 ;; If REV2 is "" then compare current buffer with REV1.
171 ;; If the current buffer is named `F', the version is named `F.~REV~'.
172 ;; If `F.~REV~' already exists, it is used instead of being re-created.
173 (let (rev1buf rev2buf)
174 (save-excursion
175 (if (or (not rev1) (string= rev1 ""))
176 (setq rev1 (generic-sc-get-latest-rev)))
177 (sc-visit-previous-revision rev1)
178 (setq rev1buf (current-buffer)))
179 (save-excursion
180 (or (string= rev2 "") ; use current buffer
181 (sc-visit-previous-revision rev2))
182 (setq rev2buf (current-buffer)))
183 (ediff-buffers rev1buf rev2buf startup-hooks 'ediff-revision)))
186 ;;; Merge with Version Control
188 (defun ediff-vc-merge-internal (rev1 rev2 ancestor-rev
189 &optional startup-hooks merge-buffer-file)
190 ;; If ANCESTOR-REV non-nil, merge with ancestor
191 (let (buf1 buf2 ancestor-buf)
192 (save-window-excursion
193 (save-excursion
194 (vc-version-other-window rev1)
195 (setq buf1 (current-buffer)))
196 (save-excursion
197 (or (string= rev2 "")
198 (vc-version-other-window rev2))
199 (setq buf2 (current-buffer)))
200 (if ancestor-rev
201 (save-excursion
202 (if (string= ancestor-rev "")
203 (setq ancestor-rev (vc-workfile-version buffer-file-name)))
204 (vc-version-other-window ancestor-rev)
205 (setq ancestor-buf (current-buffer))))
206 (setq startup-hooks
207 (cons
208 `(lambda ()
209 (ediff-delete-version-file ,(buffer-file-name buf1))
210 (or ,(string= rev2 "")
211 (ediff-delete-version-file ,(buffer-file-name buf2)))
212 (or ,(string= ancestor-rev "")
213 ,(not ancestor-rev)
214 (ediff-delete-version-file ,(buffer-file-name ancestor-buf)))
216 startup-hooks)))
217 (if ancestor-rev
218 (ediff-merge-buffers-with-ancestor
219 buf1 buf2 ancestor-buf
220 startup-hooks 'ediff-merge-revisions-with-ancestor merge-buffer-file)
221 (ediff-merge-buffers
222 buf1 buf2 startup-hooks 'ediff-merge-revisions merge-buffer-file))
225 (defun ediff-rcs-merge-internal (rev1 rev2 ancestor-rev
226 &optional
227 startup-hooks merge-buffer-file)
228 ;; If ANCESTOR-REV non-nil, merge with ancestor
229 (let (buf1 buf2 ancestor-buf)
230 (save-window-excursion
231 (setq buf1 (rcs-ediff-view-revision rev1)
232 buf2 (if (string= rev2 "")
233 (current-buffer)
234 (rcs-ediff-view-revision rev2))
235 ancestor-buf (if ancestor-rev
236 (if (string= ancestor-rev "")
237 (current-buffer)
238 (rcs-ediff-view-revision ancestor-rev)))))
239 ;; rcs.el doesn't create temp version files, so we don't have to delete
240 ;; anything in startup hooks to ediff-buffers
241 (if ancestor-rev
242 (ediff-merge-buffers-with-ancestor
243 buf1 buf2 ancestor-buf
244 startup-hooks 'ediff-merge-revisions-with-ancestor merge-buffer-file)
245 (ediff-merge-buffers
246 buf1 buf2 startup-hooks 'ediff-merge-revisions merge-buffer-file))))
248 (defun ediff-generic-sc-merge-internal (rev1 rev2 ancestor-rev
249 &optional
250 startup-hooks merge-buffer-file)
251 ;; If ANCESTOR-REV non-nil, merge with ancestor
252 (let (buf1 buf2 ancestor-buf)
253 (save-excursion
254 (if (string= rev1 "")
255 (setq rev1 (generic-sc-get-latest-rev)))
256 (sc-visit-previous-revision rev1)
257 (setq buf1 (current-buffer)))
258 (save-excursion
259 (or (string= rev2 "")
260 (sc-visit-previous-revision rev2))
261 (setq buf2 (current-buffer)))
262 (if ancestor-rev
263 (save-excursion
264 (or (string= ancestor-rev "")
265 (sc-visit-previous-revision ancestor-rev))
266 (setq ancestor-buf (current-buffer))))
267 (if ancestor-rev
268 (ediff-merge-buffers-with-ancestor
269 buf1 buf2 ancestor-buf
270 startup-hooks 'ediff-merge-revisions-with-ancestor merge-buffer-file)
271 (ediff-merge-buffers
272 buf1 buf2 startup-hooks 'ediff-merge-revisions merge-buffer-file))))
275 ;; PCL-CVS.el support
277 ;; MK: Check. This function doesn't seem to be used any more by pcvs or pcl-cvs
278 (defun cvs-run-ediff-on-file-descriptor (tin)
279 ;; This is a replacement for cvs-emerge-mode
280 ;; Runs after cvs-update.
281 ;; Ediff-merge appropriate revisions of the selected file.
282 (let* ((fileinfo (tin-cookie cvs-cookie-handle tin))
283 (type (cvs-fileinfo->type fileinfo))
284 (tmp-file
285 (cvs-retrieve-revision-to-tmpfile fileinfo))
286 (default-directory
287 (file-name-as-directory (cvs-fileinfo->dir fileinfo)))
288 ancestor-file)
290 (or (memq type '(MERGED CONFLICT MODIFIED))
291 (error
292 "Can only merge `Modified', `Merged' or `Conflict' files"))
294 (cond ((memq type '(MERGED CONFLICT))
295 (setq ancestor-file
296 (cvs-retrieve-revision-to-tmpfile
297 fileinfo
298 ;; revision
299 (cvs-fileinfo->base-revision fileinfo)))
300 (ediff-merge-buffers-with-ancestor
301 (find-file-noselect tmp-file)
302 (find-file-noselect (cvs-fileinfo->backup-file fileinfo))
303 (find-file-noselect ancestor-file)
304 nil ; startup-hooks
305 'ediff-merge-revisions-with-ancestor))
306 ((eq type 'MODIFIED)
307 (ediff-buffers
308 (find-file-noselect tmp-file)
309 (if (featurep 'xemacs)
310 ;; XEmacs doesn't seem to have cvs-fileinfo->full-name
311 (find-file-noselect (cvs-fileinfo->full-path fileinfo))
312 (find-file-noselect (cvs-fileinfo->full-name fileinfo)))
313 nil ; startup-hooks
314 'ediff-revisions)))
315 (if (stringp tmp-file) (ediff-delete-version-file tmp-file))
316 (if (stringp ancestor-file) (ediff-delete-version-file ancestor-file))))
319 ;; delete version file on exit unless ediff-keep-tmp-versions is true
320 (defun ediff-delete-version-file (file)
321 (or ediff-keep-tmp-versions (delete-file file)))
324 (provide 'ediff-vers)
327 ;;; Local Variables:
328 ;;; eval: (put 'ediff-defvar-local 'lisp-indent-hook 'defun)
329 ;;; eval: (put 'ediff-with-current-buffer 'lisp-indent-hook 1)
330 ;;; eval: (put 'ediff-with-current-buffer 'edebug-form-spec '(form body))
331 ;;; End:
333 ;;; arch-tag: bbb34f0c-2a90-426a-a77a-c75f479ebbbf
334 ;;; ediff-vers.el ends here