1;;; ediff-ptch.el --- Ediff's  patch support
2
3;; Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002,
4;;   2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
5
6;; Author: Michael Kifer <kifer@cs.stonybrook.edu>
7
8;; This file is part of GNU Emacs.
9
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.
14
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.
19
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.
24
25;;; Commentary:
26
27;;; Code:
28
29
30(defgroup ediff-ptch nil
31  "Ediff patch support."
32  :tag "Patch"
33  :prefix "ediff-"
34  :group 'ediff)
35
36;; compiler pacifier
37(defvar ediff-window-A)
38(defvar ediff-window-B)
39(defvar ediff-window-C)
40(defvar ediff-use-last-dir)
41(defvar ediff-shell)
42
43(eval-when-compile
44  (let ((load-path (cons (expand-file-name ".") load-path)))
45    (or (featurep 'ediff-init)
46	(load "ediff-init.el" nil nil 'nosuffix))
47    (or (featurep 'ediff-mult)
48	(load "ediff-mult.el" nil nil 'nosuffix))
49    (or (featurep 'ediff)
50	(load "ediff.el" nil nil 'nosuffix))
51    ))
52;; end pacifier
53
54(require 'ediff-init)
55
56(defcustom ediff-patch-program  "patch"
57  "*Name of the program that applies patches.
58It is recommended to use GNU-compatible versions."
59  :type 'string
60  :group 'ediff-ptch)
61(defcustom ediff-patch-options "-f"
62  "*Options to pass to ediff-patch-program.
63
64Note: the `-b' option should be specified in `ediff-backup-specs'.
65
66It is recommended to pass the `-f' option to the patch program, so it won't ask
67questions.  However, some implementations don't accept this option, in which
68case the default value for this variable should be changed."
69  :type 'string
70  :group 'ediff-ptch)
71
72(defvar ediff-last-dir-patch nil
73  "Last directory used by an Ediff command for file to patch.")
74
75;; the default backup extension
76(defconst ediff-default-backup-extension
77  (if (memq system-type '(vax-vms axp-vms emx ms-dos))
78      "_orig" ".orig"))
79
80
81(defcustom ediff-backup-extension ediff-default-backup-extension
82  "Backup extension used by the patch program.
83See also `ediff-backup-specs'."
84  :type 'string
85  :group 'ediff-ptch)
86
87(defun ediff-test-patch-utility ()
88  (condition-case nil
89      (cond ((eq 0 (call-process ediff-patch-program nil nil nil "-z." "-b"))
90	     ;; GNU `patch' v. >= 2.2
91	     'gnu)
92	    ((eq 0 (call-process ediff-patch-program nil nil nil "-b"))
93	     'posix)
94	    (t 'traditional))
95    (file-error nil)))
96
97(defcustom ediff-backup-specs
98  (let ((type (ediff-test-patch-utility)))
99    (cond ((eq type 'gnu)
100	   ;; GNU `patch' v. >= 2.2
101	   (format "-z%s -b" ediff-backup-extension))
102	  ((eq type 'posix)
103	   ;; POSIX `patch' -- ediff-backup-extension must be ".orig"
104	   (setq ediff-backup-extension ediff-default-backup-extension)
105	   "-b")
106	  (t
107	   ;; traditional `patch'
108	   (format "-b %s" ediff-backup-extension))))
109  "*Backup directives to pass to the patch program.
110Ediff requires that the old version of the file \(before applying the patch\)
111be saved in a file named `the-patch-file.extension'.  Usually `extension' is
112`.orig', but this can be changed by the user and may depend on the system.
113Therefore, Ediff needs to know the backup extension used by the patch program.
114
115Some versions of the patch program let you specify `-b backup-extension'.
116Other versions only permit `-b', which assumes the extension `.orig'
117\(in which case ediff-backup-extension MUST be also `.orig'\).  The latest
118versions of GNU patch require `-b -z backup-extension'.
119
120Note that both `ediff-backup-extension' and `ediff-backup-specs'
121must be set properly.  If your patch program takes the option `-b',
122but not `-b extension', the variable `ediff-backup-extension' must
123still be set so Ediff will know which extension to use.
124
125Ediff tries to guess the appropriate value for this variables.  It is believed
126to be working for `traditional' patch, all versions of GNU patch, and for POSIX
127patch.  So, don't change these variables, unless the default doesn't work."
128  :type 'string
129  :group 'ediff-ptch)
130
131
132(defcustom ediff-patch-default-directory nil
133  "*Default directory to look for patches."
134  :type '(choice (const nil) string)
135  :group 'ediff-ptch)
136
137(defcustom ediff-context-diff-label-regexp
138  (concat "\\(" 	; context diff 2-liner
139	  "^\\*\\*\\* \\([^ \t]+\\)[^*]+[\t ]*\n--- \\([^ \t]+\\)"
140	  "\\|" 	; GNU unified format diff 2-liner
141	  "^--- \\([^ \t]+\\)[\t ]+.*\n\\+\\+\\+ \\([^ \t]+\\)"
142	  "\\)")
143  "*Regexp matching filename 2-liners at the start of each context diff.
144You probably don't want to change that, unless you are using an obscure patch
145program."
146  :type 'regexp
147  :group 'ediff-ptch)
148
149;; The buffer of the patch file.  Local to control buffer.
150(ediff-defvar-local ediff-patchbufer nil "")
151
152;; The buffer where patch displays its diagnostics.
153(ediff-defvar-local ediff-patch-diagnostics nil "")
154
155;; Map of patch buffer.  Has the form:
156;;    ((filename1 marker1 marker2) (filename2 marker1 marker2) ...)
157;; where filenames are files to which patch would have applied the patch;
158;; marker1 delimits the beginning of the corresponding patch and marker2 does
159;; it for the end.
160(ediff-defvar-local ediff-patch-map nil "")
161
162;; strip prefix from filename
163;; returns /dev/null, if can't strip prefix
164(defsubst ediff-file-name-sans-prefix (filename prefix)
165  (if prefix
166      (save-match-data
167	(if (string-match (concat "^" (if (stringp prefix)
168					  (regexp-quote prefix)
169					""))
170			  filename)
171	    (substring filename (match-end 0))
172	  (concat "/null/" filename)))
173    filename)
174  )
175
176
177
178;; no longer used
179;; return the number of matches of regexp in buf starting from the beginning
180(defun ediff-count-matches (regexp buf)
181  (ediff-with-current-buffer buf
182    (let ((count 0) opoint)
183      (save-excursion
184	(goto-char (point-min))
185	(while (and (not (eobp))
186		    (progn (setq opoint (point))
187			   (re-search-forward regexp nil t)))
188	  (if (= opoint (point))
189	      (forward-char 1)
190	    (setq count (1+ count)))))
191      count)))
192
193;; Scan BUF (which is supposed to contain a patch) and make a list of the form
194;;    ((nil nil filename-spec1 marker1 marker2)
195;;          (nil nil filename-spec2 marker1 marker2) ...)
196;; where filename-spec[12] are files to which the `patch' program would
197;; have applied the patch.
198;; nin, nil are placeholders. See ediff-make-new-meta-list-element in
199;;    ediff-meta.el for the explanations.
200;; In the beginning we don't know exactly which files need to be patched.
201;; We usually come up with two candidates and ediff-file-name-sans-prefix
202;;    resolves this later.
203;;
204;; The marker `marker1' delimits the beginning of the corresponding patch and
205;;    `marker2' does it for the end.
206;; The result of ediff-map-patch-buffer is a list, which is then assigned
207;; to ediff-patch-map.
208;; The function returns the number of elements in the list ediff-patch-map
209(defun ediff-map-patch-buffer (buf)
210  (ediff-with-current-buffer buf
211    (let ((count 0)
212	  (mark1 (move-marker (make-marker) (point-min)))
213	  (mark1-end (point-min))
214	  (possible-file-names '("/dev/null" . "/dev/null"))
215	  mark2-end mark2 filenames
216	  beg1 beg2 end1 end2
217	  patch-map opoint)
218      (save-excursion
219	(goto-char (point-min))
220	(setq opoint (point))
221	(while (and (not (eobp))
222		    (re-search-forward ediff-context-diff-label-regexp nil t))
223	  (if (= opoint (point))
224	      (forward-char 1) ; ensure progress towards the end
225	    (setq mark2 (move-marker (make-marker) (match-beginning 0))
226		  mark2-end (match-end 0)
227		  beg1 (or (match-beginning 2) (match-beginning 4))
228 		  end1 (or (match-end 2) (match-end 4))
229 		  beg2 (or (match-beginning 3) (match-beginning 5))
230 		  end2 (or (match-end 3) (match-end 5)))
231	    ;; possible-file-names is holding the new file names until we
232	    ;; insert the old file name in the patch map
233	    ;; It is a pair
234	    ;;     (filename-from-1st-header-line . fn from 2nd line)
235	    (setq possible-file-names
236		  (cons (if (and beg1 end1)
237			    (buffer-substring beg1 end1)
238			  "/dev/null")
239			(if (and beg2 end2)
240			    (buffer-substring beg2 end2)
241			  "/dev/null")))
242	    ;; check for any `Index:' or `Prereq:' lines, but don't use them
243	    (if (re-search-backward "^Index:" mark1-end 'noerror)
244		(move-marker mark2 (match-beginning 0)))
245	    (if (re-search-backward "^Prereq:" mark1-end 'noerror)
246		(move-marker mark2 (match-beginning 0)))
247
248	    (goto-char mark2-end)
249
250	    (if filenames
251		(setq patch-map
252		      (cons (ediff-make-new-meta-list-element
253			     filenames mark1 mark2)
254			    patch-map)))
255	    (setq mark1 mark2
256		  mark1-end mark2-end
257		  filenames possible-file-names))
258	  (setq opoint (point)
259		count (1+ count))))
260      (setq mark2 (point-max-marker)
261	    patch-map (cons (ediff-make-new-meta-list-element
262			     possible-file-names mark1 mark2)
263			    patch-map))
264      (setq ediff-patch-map (nreverse patch-map))
265      count)))
266
267;; Fix up the file names in the list using the argument FILENAME
268;; Algorithm: find the files' directories in the patch and, if a directory is
269;; absolute, cut it out from the corresponding file name in the patch.
270;; Relative directories are not cut out.
271;; Prepend the directory of FILENAME to each resulting file (which came
272;; originally from the patch).
273;; In addition, the first file in the patch document is replaced by FILENAME.
274;; Each file is actually a pair of files found in the context diff header
275;; In the end, for each pair, we ask the user which file to patch.
276;; Note: Ediff doesn't recognize multi-file patches that are separated
277;; with the `Index:' line.  It treats them as a single-file patch.
278;;
279;; Executes inside the patch buffer
280(defun ediff-fixup-patch-map (filename)
281  (setq filename (expand-file-name filename))
282  (let ((actual-dir (if (file-directory-p filename)
283			;; directory part of filename
284			(file-name-as-directory filename)
285		      (file-name-directory filename)))
286	;; In case 2 files are possible patch targets, the user will be offered
287	;; to choose file1 or file2.  In a multifile patch, if the user chooses
288	;; 1 or 2, this choice is preserved to decide future alternatives.
289	chosen-alternative
290	)
291
292    ;; chop off base-dirs
293    (mapcar (lambda (session-info)
294	      (let* ((proposed-file-names
295		      ;; Filename-spec is objA; it is represented as
296		      ;; (file1 . file2). Get it using ediff-get-session-objA.
297		      (ediff-get-session-objA-name session-info))
298		     ;; base-dir1 is  the dir part of the 1st file in the patch
299		     (base-dir1
300		      (or (file-name-directory (car proposed-file-names))
301			  ""))
302		     ;; directory part of the 2nd file in the patch
303		     (base-dir2
304		      (or (file-name-directory (cdr proposed-file-names))
305			  ""))
306		     )
307		;; If both base-dir1 and base-dir2 are relative and exist,
308		;; assume that
309		;; these dirs lead to the actual files starting at the present
310		;; directory. So, we don't strip these relative dirs from the
311		;; file names. This is a heuristic intended to improve guessing
312		(unless (or (file-name-absolute-p base-dir1)
313			    (file-name-absolute-p base-dir2)
314			    (not (file-exists-p base-dir1))
315			    (not (file-exists-p base-dir2)))
316		  (setq base-dir1 ""
317			base-dir2 ""))
318		(or (string= (car proposed-file-names) "/dev/null")
319		    (setcar proposed-file-names
320			    (ediff-file-name-sans-prefix
321			     (car proposed-file-names) base-dir1)))
322		(or (string=
323		     (cdr proposed-file-names) "/dev/null")
324		    (setcdr proposed-file-names
325			    (ediff-file-name-sans-prefix
326			     (cdr proposed-file-names) base-dir2)))
327		))
328	    ediff-patch-map)
329
330    ;; take the given file name into account
331    (or (file-directory-p filename)
332	(string= "/dev/null" filename)
333	(setcar (ediff-get-session-objA (car ediff-patch-map))
334		(cons (file-name-nondirectory filename)
335		      (file-name-nondirectory filename))))
336
337    ;; prepend actual-dir
338    (mapcar (lambda (session-info)
339	      (let ((proposed-file-names
340		     (ediff-get-session-objA-name session-info)))
341		(if (and (string-match "^/null/" (car proposed-file-names))
342			 (string-match "^/null/" (cdr proposed-file-names)))
343		    ;; couldn't intuit the file name to patch, so
344		    ;; something is amiss
345		    (progn
346		      (with-output-to-temp-buffer ediff-msg-buffer
347			(ediff-with-current-buffer standard-output
348			  (fundamental-mode))
349			(princ
350			 (format "
351The patch file contains a context diff for
352	%s
353	%s
354However, Ediff cannot infer the name of the actual file
355to be patched on your system.  If you know the correct file name,
356please enter it now.
357
358If you don't know and still would like to apply patches to
359other files, enter /dev/null
360"
361				 (substring (car proposed-file-names) 6)
362				 (substring (cdr proposed-file-names) 6))))
363		      (let ((directory t)
364			    user-file)
365			(while directory
366			  (setq user-file
367				(read-file-name
368				 "Please enter file name: "
369				 actual-dir actual-dir t))
370			  (if (not (file-directory-p user-file))
371			      (setq directory nil)
372			    (setq directory t)
373			    (beep)
374			    (message "%s is a directory" user-file)
375			    (sit-for 2)))
376			(setcar (ediff-get-session-objA session-info)
377				(cons user-file user-file))))
378		  (setcar proposed-file-names
379			  (expand-file-name
380			   (concat actual-dir (car proposed-file-names))))
381		  (setcdr proposed-file-names
382			  (expand-file-name
383			   (concat actual-dir (cdr proposed-file-names)))))
384		))
385	    ediff-patch-map)
386    ;; Check for the existing files in each pair and discard the nonexisting
387    ;; ones. If both exist, ask the user.
388    (mapcar (lambda (session-info)
389	      (let* ((file1 (car (ediff-get-session-objA-name session-info)))
390		     (file2 (cdr (ediff-get-session-objA-name session-info)))
391		     (session-file-object
392		      (ediff-get-session-objA session-info))
393		     (f1-exists (file-exists-p file1))
394		     (f2-exists (file-exists-p file2)))
395		(cond
396		 ((and
397		   ;; The patch program prefers the shortest file as the patch
398		   ;; target. However, this is a questionable heuristic. In an
399		   ;; interactive program, like ediff, we can offer the user a
400		   ;; choice.
401		   ;; (< (length file2) (length file1))
402		   (not f1-exists)
403		   f2-exists)
404		  ;; replace file-pair with the winning file2
405		  (setcar session-file-object file2))
406		 ((and
407		   ;; (< (length file1) (length file2))
408		   (not f2-exists)
409		   f1-exists)
410		  ;; replace file-pair with the winning file1
411		  (setcar session-file-object file1))
412		 ((and f1-exists f2-exists
413		       (string= file1 file2))
414		  (setcar session-file-object file1))
415		 ((and f1-exists f2-exists (eq chosen-alternative 1))
416		  (setcar session-file-object file1))
417		 ((and f1-exists f2-exists (eq chosen-alternative 2))
418		  (setcar session-file-object file2))
419		 ((and f1-exists f2-exists)
420		  (with-output-to-temp-buffer ediff-msg-buffer
421		    (ediff-with-current-buffer standard-output
422		      (fundamental-mode))
423		    (princ (format "
424Ediff has inferred that
425	%s
426	%s
427are two possible targets for applying the patch.
428Both files seem to be plausible alternatives.
429
430Please advice:
431    Type `y' to use %s as the target;
432    Type `n' to use %s as the target.
433"
434				   file1 file2 file1 file2)))
435		  (setcar session-file-object
436			  (if (y-or-n-p (format "Use %s ? " file1))
437			      (progn
438				(setq chosen-alternative 1)
439				file1)
440			    (setq chosen-alternative 2)
441			    file2))
442		  )
443		 (f2-exists (setcar session-file-object file2))
444		 (f1-exists (setcar session-file-object file1))
445		 (t
446		  (with-output-to-temp-buffer ediff-msg-buffer
447		    (ediff-with-current-buffer standard-output
448		      (fundamental-mode))
449		    (princ "\nEdiff has inferred that")
450		    (if (string= file1 file2)
451			(princ (format "
452	%s
453is assumed to be the target for this patch.  However, this file does not exist."
454				       file1))
455		      (princ (format "
456	%s
457	%s
458are two possible targets for this patch.  However, these files do not exist."
459				     file1 file2)))
460		    (princ "
461\nPlease enter an alternative patch target ...\n"))
462		  (let ((directory t)
463			target)
464		    (while directory
465		      (setq target (read-file-name
466				    "Please enter a patch target: "
467				    actual-dir actual-dir t))
468		      (if (not (file-directory-p target))
469			  (setq directory nil)
470			(beep)
471			(message "%s is a directory" target)
472			(sit-for 2)))
473		    (setcar session-file-object target))))))
474	    ediff-patch-map)
475    ))
476
477(defun ediff-show-patch-diagnostics ()
478  (interactive)
479  (cond ((window-live-p ediff-window-A)
480	 (set-window-buffer ediff-window-A ediff-patch-diagnostics))
481	((window-live-p ediff-window-B)
482	 (set-window-buffer ediff-window-B ediff-patch-diagnostics))
483	(t (display-buffer ediff-patch-diagnostics 'not-this-window))))
484
485;; prompt for file, get the buffer
486(defun ediff-prompt-for-patch-file ()
487  (let ((dir (cond (ediff-use-last-dir ediff-last-dir-patch)
488		   (ediff-patch-default-directory) ; try patch default dir
489		   (t default-directory)))
490	(coding-system-for-read ediff-coding-system-for-read)
491	patch-file-name)
492    (setq patch-file-name
493	  (read-file-name
494	   (format "Patch is in file%s: "
495		   (cond ((and buffer-file-name
496			       (equal (expand-file-name dir)
497				      (file-name-directory buffer-file-name)))
498			  (concat
499			   " (default "
500			   (file-name-nondirectory buffer-file-name)
501			   ")"))
502			 (t "")))
503	   dir buffer-file-name 'must-match))
504    (if (file-directory-p patch-file-name)
505	(error "Patch file cannot be a directory: %s" patch-file-name)
506      (find-file-noselect patch-file-name))
507    ))
508
509
510;; Try current buffer, then the other window's buffer. Else, give up.
511(defun ediff-prompt-for-patch-buffer ()
512  (get-buffer
513   (read-buffer
514    "Buffer that holds the patch: "
515    (cond ((save-excursion
516	     (goto-char (point-min))
517	     (re-search-forward ediff-context-diff-label-regexp nil t))
518	   (current-buffer))
519	  ((save-window-excursion
520	     (other-window 1)
521	     (save-excursion
522	       (goto-char (point-min))
523	       (and (re-search-forward ediff-context-diff-label-regexp nil t)
524		    (current-buffer)))))
525	  ((save-window-excursion
526	     (other-window -1)
527	     (save-excursion
528	       (goto-char (point-min))
529	       (and (re-search-forward ediff-context-diff-label-regexp nil t)
530		    (current-buffer)))))
531	  (t (ediff-other-buffer (current-buffer))))
532    'must-match)))
533
534
535(defun ediff-get-patch-buffer (&optional arg patch-buf)
536  "Obtain patch buffer.  If patch is already in a buffer---use it.
537Else, read patch file into a new buffer. If patch buffer is passed as an
538optional argument, then use it."
539  (let ((last-nonmenu-event t) ; Emacs: don't use dialog box
540	last-command-event)    ; XEmacs: don't use dialog box
541
542    (cond ((ediff-buffer-live-p patch-buf))
543	  ;; even prefix arg: patch in buffer
544	  ((and (integerp arg) (eq 0 (mod arg 2)))
545	   (setq patch-buf (ediff-prompt-for-patch-buffer)))
546	  ;; odd prefix arg: get patch from a file
547	  ((and (integerp arg) (eq 1 (mod arg 2)))
548	   (setq patch-buf (ediff-prompt-for-patch-file)))
549	  (t (setq patch-buf
550		   (if (y-or-n-p "Is the patch already in a buffer? ")
551		       (ediff-prompt-for-patch-buffer)
552		     (ediff-prompt-for-patch-file)))))
553
554    (ediff-with-current-buffer patch-buf
555      (goto-char (point-min))
556      (or (ediff-get-visible-buffer-window patch-buf)
557	  (progn
558	    (pop-to-buffer patch-buf 'other-window)
559	    (select-window (previous-window)))))
560    (ediff-map-patch-buffer patch-buf)
561    patch-buf))
562
563;; Dispatch the right patch file function: regular or meta-level,
564;; depending on how many patches are in the patch file.
565;; At present, there is no support for meta-level patches.
566;; Should return either the ctl buffer or the meta-buffer
567(defun ediff-dispatch-file-patching-job (patch-buf filename
568						   &optional startup-hooks)
569  (ediff-with-current-buffer patch-buf
570    ;; relativize names in the patch with respect to source-file
571    (ediff-fixup-patch-map filename)
572    (if (< (length ediff-patch-map) 2)
573	(ediff-patch-file-internal
574	 patch-buf
575	 (if (and ediff-patch-map
576		  (not (string-match
577			"^/dev/null"
578			;; this is the file to patch
579			(ediff-get-session-objA-name (car ediff-patch-map))))
580		  (> (length
581		      (ediff-get-session-objA-name (car ediff-patch-map)))
582		     1))
583	     (ediff-get-session-objA-name (car ediff-patch-map))
584	   filename)
585	 startup-hooks)
586      (ediff-multi-patch-internal patch-buf startup-hooks))
587    ))
588
589
590;; When patching a buffer, never change the orig file.  Instead, create a new
591;; buffer, ***_patched, even if the buff visits a file.
592;; Users who want to actually patch the buffer should use
593;; ediff-patch-file, not ediff-patch-buffer.
594(defun ediff-patch-buffer-internal (patch-buf
595				    buf-to-patch-name
596				    &optional startup-hooks)
597  (let* ((buf-to-patch (get-buffer buf-to-patch-name))
598	 (visited-file (if buf-to-patch (buffer-file-name  buf-to-patch)))
599	 (buf-mod-status (buffer-modified-p buf-to-patch))
600	 (multifile-patch-p (> (length (ediff-with-current-buffer patch-buf
601					 ediff-patch-map)) 1))
602	 default-dir file-name ctl-buf)
603    (if multifile-patch-p
604	(error
605	 "To apply multi-file patches, please use `ediff-patch-file'"))
606
607    ;; create a temp file to patch
608    (ediff-with-current-buffer buf-to-patch
609      (setq default-dir default-directory)
610      (setq file-name (ediff-make-temp-file buf-to-patch))
611      ;; temporarily switch visited file name, if any
612      (set-visited-file-name file-name)
613      ;; don't create auto-save file, if buff was visiting a file
614      (or visited-file
615	  (setq buffer-auto-save-file-name nil))
616      ;; don't confuse the user with a new bufname
617      (rename-buffer buf-to-patch-name)
618      (set-buffer-modified-p nil)
619      (set-visited-file-modtime) ; sync buffer and temp file
620      (setq default-directory default-dir)
621      )
622
623    ;; dispatch a patch function
624    (setq ctl-buf (ediff-dispatch-file-patching-job
625		   patch-buf file-name startup-hooks))
626
627    (ediff-with-current-buffer ctl-buf
628      (delete-file (buffer-file-name ediff-buffer-A))
629      (delete-file (buffer-file-name ediff-buffer-B))
630      (ediff-with-current-buffer ediff-buffer-A
631	(if default-dir (setq default-directory default-dir))
632	(set-visited-file-name visited-file) ; visited-file might be nil
633	(rename-buffer buf-to-patch-name)
634	(set-buffer-modified-p buf-mod-status))
635      (ediff-with-current-buffer ediff-buffer-B
636	(setq buffer-auto-save-file-name nil) ; don't create auto-save file
637	(if default-dir (setq default-directory default-dir))
638	(set-visited-file-name nil)
639	(rename-buffer (ediff-unique-buffer-name
640			(concat buf-to-patch-name "_patched") ""))
641	(set-buffer-modified-p t)))
642    ))
643
644
645;; Traditional patch has weird return codes.
646;; GNU and Posix return 1 if some hanks failed and 2 in case of trouble.
647;; 0 is a good code in all cases.
648;; We'll do the concervative thing.
649(defun ediff-patch-return-code-ok (code)
650  (eq code 0))
651;;;  (if (eq (ediff-test-patch-utility) 'traditional)
652;;;      (eq code 0)
653;;;    (not (eq code 2))))
654
655(defun ediff-patch-file-internal (patch-buf source-filename
656					    &optional startup-hooks)
657  (setq source-filename (expand-file-name source-filename))
658
659  (let* ((shell-file-name ediff-shell)
660	 (patch-diagnostics (get-buffer-create "*ediff patch diagnostics*"))
661	 ;; ediff-find-file may use a temp file to do the patch
662	 ;; so, we save source-filename and true-source-filename as a var
663	 ;; that initially is source-filename but may be changed to a temp
664	 ;; file for the purpose of patching.
665	 (true-source-filename source-filename)
666	 (target-filename source-filename)
667	 ;; this ensures that the patch process gets patch buffer in the
668	 ;; encoding that Emacs thinks is right for that type of text
669	 (coding-system-for-write
670	  (if (boundp 'buffer-file-coding-system) buffer-file-coding-system))
671	 target-buf buf-to-patch file-name-magic-p
672	 patch-return-code ctl-buf backup-style aux-wind)
673
674    (if (string-match "V" ediff-patch-options)
675	(error
676	 "Ediff doesn't take the -V option in `ediff-patch-options'--sorry"))
677
678    ;; Make a temp file, if source-filename has a magic file handler (or if
679    ;; it is handled via auto-mode-alist and similar magic).
680    ;; Check if there is a buffer visiting source-filename and if they are in
681    ;; sync; arrange for the deletion of temp file.
682    (ediff-find-file 'true-source-filename 'buf-to-patch
683		     'ediff-last-dir-patch 'startup-hooks)
684
685    ;; Check if source file name has triggered black magic, such as file name
686    ;; handlers or auto mode alist, and make a note of it.
687    ;; true-source-filename should be either the original name or a
688    ;; temporary file where we put the after-product of the file handler.
689    (setq file-name-magic-p (not (equal (file-truename true-source-filename)
690					(file-truename source-filename))))
691
692    ;; Checkout orig file, if necessary, so that the patched file
693    ;; could be checked back in.
694    (ediff-maybe-checkout buf-to-patch)
695
696    (ediff-with-current-buffer patch-diagnostics
697      (insert-buffer-substring patch-buf)
698      (message "Applying patch ... ")
699      ;; fix environment for gnu patch, so it won't make numbered extensions
700      (setq backup-style (getenv "VERSION_CONTROL"))
701      (setenv "VERSION_CONTROL" nil)
702      (setq patch-return-code
703	    (call-process-region
704	     (point-min) (point-max)
705	     shell-file-name
706	     t   ; delete region (which contains the patch
707	     t   ; insert output (patch diagnostics) in current buffer
708	     nil ; don't redisplay
709	     shell-command-switch   ; usually -c
710	     (format "%s %s %s %s"
711		     ediff-patch-program
712		     ediff-patch-options
713		     ediff-backup-specs
714		     (expand-file-name true-source-filename))
715	     ))
716
717      ;; restore environment for gnu patch
718      (setenv "VERSION_CONTROL" backup-style))
719
720    (message "Applying patch ... done")
721    (message "")
722
723    (switch-to-buffer patch-diagnostics)
724    (sit-for 0) ; synchronize - let the user see diagnostics
725
726    (or (and (ediff-patch-return-code-ok patch-return-code)
727	     (file-exists-p
728	      (concat true-source-filename ediff-backup-extension)))
729	(progn
730	  (with-output-to-temp-buffer ediff-msg-buffer
731	    (ediff-with-current-buffer standard-output
732	      (fundamental-mode))
733	    (princ (format
734		    "Patch program has failed due to a bad patch file,
735it couldn't apply all hunks, OR
736it couldn't create the backup for the file being patched.
737
738The former could be caused by a corrupt patch file or because the %S
739program doesn't understand the format of the patch file in use.
740
741The second problem might be due to an incompatibility among these settings:
742    ediff-patch-program    = %S             ediff-patch-options    = %S
743    ediff-backup-extension = %S             ediff-backup-specs     = %S
744
745See Ediff on-line manual for more details on these variables.
746In particular, check the documentation for `ediff-backup-specs'.
747
748In any of the above cases, Ediff doesn't compare files automatically.
749However, if the patch was applied partially and the backup file was created,
750you can still examine the changes via M-x ediff-files"
751		    ediff-patch-program
752		    ediff-patch-program
753		    ediff-patch-options
754		    ediff-backup-extension
755		    ediff-backup-specs
756		    )))
757	  (beep 1)
758	  (if (setq aux-wind (get-buffer-window ediff-msg-buffer))
759	      (progn
760		(select-window aux-wind)
761		(goto-char (point-max))))
762	  (switch-to-buffer-other-window patch-diagnostics)
763	  (error "Patch appears to have failed")))
764
765    ;; If black magic is involved, apply patch to a temp copy of the
766    ;; file.  Otherwise, apply patch to the orig copy.  If patch is applied
767    ;; to temp copy, we name the result old-name_patched for local files
768    ;; and temp-copy_patched for remote files.  The orig file name isn't
769    ;; changed, and the temp copy of the original is later deleted.
770    ;; Without magic, the original file is renamed (usually into
771    ;; old-name_orig) and the result of patching will have the same name as
772    ;; the original.
773    (if (not file-name-magic-p)
774	(ediff-with-current-buffer buf-to-patch
775	  (set-visited-file-name
776	   (concat source-filename ediff-backup-extension))
777	  (set-buffer-modified-p nil))
778
779      ;; Black magic in effect.
780      ;; If orig file was remote, put the patched file in the temp directory.
781      ;; If orig file is local, put the patched file in the directory of
782      ;; the orig file.
783      (setq target-filename
784	    (concat
785	     (if (ediff-file-remote-p (file-truename source-filename))
786		 true-source-filename
787	       source-filename)
788	     "_patched"))
789
790      (rename-file true-source-filename target-filename t)
791
792      ;; arrange that the temp copy of orig will be deleted
793      (rename-file (concat true-source-filename ediff-backup-extension)
794		   true-source-filename t))
795
796    ;; make orig buffer read-only
797    (setq startup-hooks
798	  (cons 'ediff-set-read-only-in-buf-A startup-hooks))
799
800    ;; set up a buf for the patched file
801    (setq target-buf (find-file-noselect target-filename))
802
803    (setq ctl-buf
804	  (ediff-buffers-internal
805	   buf-to-patch target-buf nil
806	   startup-hooks 'epatch))
807    (ediff-with-current-buffer ctl-buf
808      (setq ediff-patchbufer patch-buf
809	    ediff-patch-diagnostics patch-diagnostics))
810
811    (bury-buffer patch-diagnostics)
812    (message "Type `P', if you need to see patch diagnostics")
813    ctl-buf))
814
815(defun ediff-multi-patch-internal (patch-buf &optional startup-hooks)
816  (let (meta-buf)
817    (setq startup-hooks
818	  ;; this sets various vars in the meta buffer inside
819	  ;; ediff-prepare-meta-buffer
820	  (cons `(lambda ()
821		   ;; tell what to do if the user clicks on a session record
822		   (setq ediff-session-action-function
823			 'ediff-patch-file-form-meta
824			 ediff-meta-patchbufer patch-buf) )
825		startup-hooks))
826    (setq meta-buf (ediff-prepare-meta-buffer
827		    'ediff-filegroup-action
828		    (ediff-with-current-buffer patch-buf
829		      (cons (ediff-make-new-meta-list-header
830			     nil                     ; regexp
831			     (format "%S" patch-buf) ; obj A
832			     nil nil                 ; objects B,C
833			     nil                     ; merge-auto-store-dir
834			     nil                     ; comparison-func
835			     )
836			    ediff-patch-map))
837		    "*Ediff Session Group Panel"
838		    'ediff-redraw-directory-group-buffer
839		    'ediff-multifile-patch
840		    startup-hooks))
841    (ediff-show-meta-buffer meta-buf)
842    ))
843
844
845
846(provide 'ediff-ptch)
847
848
849;;; Local Variables:
850;;; eval: (put 'ediff-defvar-local 'lisp-indent-hook 'defun)
851;;; eval: (put 'ediff-with-current-buffer 'lisp-indent-hook 1)
852;;; eval: (put 'ediff-with-current-buffer 'edebug-form-spec '(form body))
853;;; End:
854
855;;; arch-tag: 2fe2161e-e116-469b-90fa-5cbb44c1bd1b
856;;; ediff-ptch.el ends here
857