[bpt/emacs.git] / lisp / diff.el

;;; diff.el --- "DIFF" mode for handling output from unix diff utility.

;; Copyright (C) 1990 Free Software Foundation, Inc.

;; Author: Frank P. Bresz <fpb@ittc.wec.com>
;; Maintainer: FSF
;; Created: 27 Jan 1989
;; Keyword: unix, tools

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to
;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

;;; Commentary:

;; todo: diff-switches flexibility:
;; (defconst diff-switches-function
;;   '(lambda (file)
;;     (if (string-match "\\.el$" file)
;; 	 "-c -F\"^(\""
;;       "-p"))
;;  "Function to return switches to pass to the `diff' utility, in \\[diff].
;; This function is called with one arg, a file name, and returns a string
;; containing 0 or more arguments which are passed on to `diff'.
;; NOTE: This is not an ordinary hook; it may not be a list of functions.")

;;  - fpb@ittc.wec.com - Sep 25, 1990
;; Added code to support sccs diffing.
;; also fixed one minor glitch in the
;; search for the pattern.  If you only 1 addition you won't find the end
;; of the pattern (minor)

;;; Code:

(defvar diff-switches nil
  "*A list of switches to pass to the diff program.")

(defvar diff-search-pattern "^\\([0-9]\\|\\*\\*\\*\\*\\*\\*\\*\\*\\*\\*\\*\\*\\*\\*\\*\\)"
  "Regular expression that delineates difference regions in diffs.")

(defvar diff-rcs-extension ",v"
  "*Extension to find RCS file, some systems do not use ,v")

;; Initialize the keymap if it isn't already
(if (boundp 'diff-mode-map)
    nil
  (setq diff-mode-map (make-keymap))
  (suppress-keymap diff-mode-map)
  (define-key diff-mode-map "?" 'describe-mode)
  (define-key diff-mode-map "." 'diff-beginning-of-diff)
  (define-key diff-mode-map " " 'scroll-up)
  (define-key diff-mode-map "\177" 'scroll-down)
  (define-key diff-mode-map "n" 'diff-next-difference)
  (define-key diff-mode-map "p" 'diff-previous-difference)
  (define-key diff-mode-map "j" 'diff-show-difference))

;;;###autoload
(defun diff (old new)
  "Find and display the differences between OLD and NEW files.
Interactively the current buffer's file name is the default for for NEW
and a backup file for NEW is the default for OLD."
  (interactive
   (let (oldf newf)
     (reverse
      (list
       (setq newf (buffer-file-name)
	     newf (if (and newf (file-exists-p newf))
			  (read-file-name
			   (concat "Diff new file: ("
				   (file-name-nondirectory newf) ") ")
			   nil newf t)
			(read-file-name "Diff new file: " nil nil t)))
       (setq oldf (file-newest-backup newf)
	     oldf (if (and oldf (file-exists-p oldf))
			  (read-file-name
			   (concat "Diff original file: ("
				   (file-name-nondirectory oldf) ") ")
			   (file-name-directory oldf) oldf t)
			(read-file-name "Diff original file: "
					(file-name-directory newf) nil t)))))))
  (message "Comparing files %s %s..." new old)
  (setq new (expand-file-name new)
	old (expand-file-name old))
  (diff-internal-diff "diff" (append diff-switches (list new old)) nil))

(defun diff-sccs (new)
  "Find and display the differences between OLD and SCCS files."
  (interactive
   (let (newf)
      (list
       (setq newf (buffer-file-name)
	     newf (if (and newf (file-exists-p newf))
			  (read-file-name
			   (concat "Diff new file: ("
				   (file-name-nondirectory newf) ") ")
			   nil newf t)
			(read-file-name "Diff new file: " nil nil t))))))

  (message "Comparing SCCS file %s..." new)
  (setq new (expand-file-name new))
  (if (file-exists-p (concat
		      (file-name-directory new)
		      "SCCS/s."
		      (file-name-nondirectory new)))
      (diff-internal-diff "sccs"
			  (append '("diffs") diff-switches (list new))
			  2)
    (error "%s does not exist"
	   (concat (file-name-directory new) "SCCS/s."
		   (file-name-nondirectory new)))))

(defun diff-rcs (new)
  "Find and display the differences between OLD and RCS files."
  (interactive
   (let (newf)
      (list
       (setq newf (buffer-file-name)
	     newf (if (and newf (file-exists-p newf))
			  (read-file-name
			   (concat "Diff new file: ("
				   (file-name-nondirectory newf) ") ")
			   nil newf t)
			(read-file-name "Diff new file: " nil nil t))))))

  (message "Comparing RCS file %s..." new)
  (let* ((fullname (expand-file-name new))
       (rcsfile (concat (file-name-directory fullname)
                       "RCS/"
                       (file-name-nondirectory fullname)
                       diff-rcs-extension)))
    (if (file-exists-p rcsfile)
      (diff-internal-diff "rcsdiff" (append diff-switches (list fullname)) 4)
      (error "%s does not exist" rcsfile))))

(defun diff-internal-diff (diff-command sw strip)
  (let ((buffer-read-only nil))
    (with-output-to-temp-buffer "*Diff Output*"
      (buffer-disable-undo standard-output)
      (save-excursion
	(set-buffer standard-output)
	(erase-buffer)
	(apply 'call-process diff-command nil t nil sw)))
    (set-buffer "*Diff Output*")
    (goto-char (point-min))
    (while sw
      (if (string= (car sw) "-c")
	  ;; strip leading filenames from context diffs
	  (progn (forward-line 2) (delete-region (point-min) (point))))
      (if (and (string= (car sw) "-C") (string= "sccs" diff-command))
	  ;; strip stuff from SCCS context diffs
	  (progn (forward-line 2) (delete-region (point-min) (point))))
      (setq sw (cdr sw)))
    (if strip
	;; strip stuff from SCCS context diffs
	(progn (forward-line strip) (delete-region (point-min) (point)))))
  (diff-mode)
  (if (string= "0" diff-total-differences)
      (let ((buffer-read-only nil))
	(insert (message "There are no differences.")))
    (narrow-to-region (point) (progn
				(forward-line 1)
				(if (re-search-forward diff-search-pattern
						       nil t)
				    (goto-char (match-beginning 0))
				  (goto-char (point-max)))))
    (setq diff-current-difference "1")))

;; Take a buffer full of Unix diff output and go into a mode to easily
;; see the next and previous difference
(defun diff-mode ()
  "Diff Mode is used by \\[diff] for perusing the output from the diff program.
All normal editing commands are turned off.  Instead, these are available:
\\<diff-mode-map>
\\[diff-beginning-of-diff]	Move point to start of this difference.
\\[scroll-up]	Scroll to next screen of this difference.
\\[scroll-down]	Scroll to previous screen of this difference.
\\[diff-next-difference]	Move to Next Difference.
\\[diff-previous-difference]	Move to Previous Difference.
\\[diff-show-difference]	Jump to difference specified by numeric position.
"
  (interactive)
  (use-local-map diff-mode-map)
  (setq buffer-read-only t
	major-mode 'diff-mode
	mode-name "Diff"
	mode-line-modified "--- "
	mode-line-process
	'(" " diff-current-difference "/" diff-total-differences))
  (make-local-variable 'diff-current-difference)
  (set (make-local-variable 'diff-total-differences)
       (int-to-string (diff-count-differences))))

(defun diff-next-difference (n)
  "Go to the beginning of the next difference.
Differences are delimited by `diff-search-pattern'."
  (interactive "p")
  (if (< n 0) (diff-previous-difference (- n))
    (if (zerop n) ()
      (goto-char (point-min))
      (forward-line 1) ; to get past the match for the start of this diff
      (widen)
      (if (re-search-forward diff-search-pattern nil 'move n)
	  (let ((start (goto-char (match-beginning 0))))
	    (forward-line 1)
	    (if (re-search-forward diff-search-pattern nil 'move)
		(goto-char (match-beginning 0)))
	    (narrow-to-region start (point))
	    (setq diff-current-difference
		  (int-to-string (+ n (string-to-int
				       diff-current-difference)))))
	(re-search-backward diff-search-pattern nil)
	(narrow-to-region (point) (point-max))
	(message "No following differences.")
	(setq diff-current-difference diff-total-differences))
      (goto-char (point-min)))))

(defun diff-previous-difference (n)
  "Go the the beginning of the previous difference.
Differences are delimited by `diff-search-pattern'."
  (interactive "p")
  (if (< n 0) (diff-next-difference (- n))
    (if (zerop n) ()
      (goto-char (point-min))
      (widen)
      (if (re-search-backward diff-search-pattern nil 'move n)
	  (setq diff-current-difference
		(int-to-string (- (string-to-int diff-current-difference) n)))
	(message "No previous differences.")
	(setq diff-current-difference "1"))
      (narrow-to-region (point) (progn
				  (forward-line 1)
				  (re-search-forward diff-search-pattern nil)
				  (goto-char (match-beginning 0))))
      (goto-char (point-min)))))

(defun diff-show-difference (n)
  "Show difference number N (prefix argument)."
  (interactive "p")
  (let ((cur (string-to-int diff-current-difference)))
    (cond ((or (= n cur)
	       (zerop n)
	       (not (natnump n))) ; should signal an error perhaps.
	   ;; just redisplay.
	   (goto-char (point-min)))
	  ((< n cur)
	   (diff-previous-difference (- cur n)))
	  ((> n cur)
	   (diff-next-difference (- n cur))))))

(defun diff-beginning-of-diff ()
  "Go to beginning of current difference."
  (interactive)
  (goto-char (point-min)))

;; This function counts up the number of differences in the buffer.
(defun diff-count-differences ()
  "Count number of differences in the current buffer."
  (message "Counting differences...")
  (save-excursion
    (save-restriction
      (widen)
      (goto-char (point-min))
      (let ((cnt 0))
	(while (re-search-forward diff-search-pattern nil t)
	  (setq cnt (1+ cnt)))
	(message "Counting differences...done (%d)" cnt)
	cnt))))

;;; diff.el ends here
Commit	Line	Data
c0274f38 ER	1	;;; diff.el --- "DIFF" mode for handling output from unix diff utility.
c0274f38 ER	2
3a801d0c ER	3	;; Copyright (C) 1990 Free Software Foundation, Inc.
3a801d0c ER	4
e5167999 ER	5	;; Author: Frank P. Bresz <fpb@ittc.wec.com>
	6	;; Maintainer: FSF
	7	;; Created: 27 Jan 1989
fd7fa35a	8	;; Keyword: unix, tools
e5167999	9
b10a4379 JB	10	;; This file is part of GNU Emacs.
	11
	12	;; GNU Emacs is free software; you can redistribute it and/or modify
	13	;; it under the terms of the GNU General Public License as published by
e5167999	14	;; the Free Software Foundation; either version 2, or (at your option)
b10a4379 JB	15	;; any later version.
	16
	17	;; GNU Emacs is distributed in the hope that it will be useful,
	18	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	19	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	20	;; GNU General Public License for more details.
	21
	22	;; You should have received a copy of the GNU General Public License
	23	;; along with GNU Emacs; see the file COPYING. If not, write to
	24	;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
	25
e5167999 ER	26	;;; Commentary:
e5167999 ER	27
b10a4379 JB	28	;; todo: diff-switches flexibility:
	29	;; (defconst diff-switches-function
	30	;; '(lambda (file)
	31	;; (if (string-match "\\.el$" file)
	32	;; "-c -F\"^(\""
	33	;; "-p"))
	34	;; "Function to return switches to pass to the `diff' utility, in \\[diff].
	35	;; This function is called with one arg, a file name, and returns a string
	36	;; containing 0 or more arguments which are passed on to `diff'.
	37	;; NOTE: This is not an ordinary hook; it may not be a list of functions.")
	38
aa228418 JB	39	;; - fpb@ittc.wec.com - Sep 25, 1990
	40	;; Added code to support sccs diffing.
	41	;; also fixed one minor glitch in the
	42	;; search for the pattern. If you only 1 addition you won't find the end
	43	;; of the pattern (minor)
	44
e5167999 ER	45	;;; Code:
e5167999 ER	46
b10a4379 JB	47	(defvar diff-switches nil
	48	"*A list of switches to pass to the diff program.")
	49
	50	(defvar diff-search-pattern "^\\([0-9]\\\|\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*\\)"
	51	"Regular expression that delineates difference regions in diffs.")
	52
aa228418 JB	53	(defvar diff-rcs-extension ",v"
	54	"*Extension to find RCS file, some systems do not use ,v")
	55
b10a4379 JB	56	;; Initialize the keymap if it isn't already
	57	(if (boundp 'diff-mode-map)
	58	nil
	59	(setq diff-mode-map (make-keymap))
	60	(suppress-keymap diff-mode-map)
	61	(define-key diff-mode-map "?" 'describe-mode)
	62	(define-key diff-mode-map "." 'diff-beginning-of-diff)
	63	(define-key diff-mode-map " " 'scroll-up)
	64	(define-key diff-mode-map "\177" 'scroll-down)
	65	(define-key diff-mode-map "n" 'diff-next-difference)
	66	(define-key diff-mode-map "p" 'diff-previous-difference)
	67	(define-key diff-mode-map "j" 'diff-show-difference))
	68
	69	;;;###autoload
	70	(defun diff (old new)
	71	"Find and display the differences between OLD and NEW files.
9c50f912 RS	72	Interactively the current buffer's file name is the default for for NEW
9c50f912 RS	73	and a backup file for NEW is the default for OLD."
b10a4379 JB	74	(interactive
	75	(let (oldf newf)
	76	(reverse
	77	(list
	78	(setq newf (buffer-file-name)
	79	newf (if (and newf (file-exists-p newf))
	80	(read-file-name
	81	(concat "Diff new file: ("
	82	(file-name-nondirectory newf) ") ")
	83	nil newf t)
	84	(read-file-name "Diff new file: " nil nil t)))
	85	(setq oldf (file-newest-backup newf)
	86	oldf (if (and oldf (file-exists-p oldf))
	87	(read-file-name
	88	(concat "Diff original file: ("
	89	(file-name-nondirectory oldf) ") ")
	90	(file-name-directory oldf) oldf t)
	91	(read-file-name "Diff original file: "
	92	(file-name-directory newf) nil t)))))))
	93	(message "Comparing files %s %s..." new old)
	94	(setq new (expand-file-name new)
	95	old (expand-file-name old))
aa228418 JB	96	(diff-internal-diff "diff" (append diff-switches (list new old)) nil))
	97
	98	(defun diff-sccs (new)
	99	"Find and display the differences between OLD and SCCS files."
	100	(interactive
	101	(let (newf)
	102	(list
	103	(setq newf (buffer-file-name)
	104	newf (if (and newf (file-exists-p newf))
	105	(read-file-name
	106	(concat "Diff new file: ("
	107	(file-name-nondirectory newf) ") ")
	108	nil newf t)
	109	(read-file-name "Diff new file: " nil nil t))))))
	110
	111	(message "Comparing SCCS file %s..." new)
	112	(setq new (expand-file-name new))
	113	(if (file-exists-p (concat
	114	(file-name-directory new)
	115	"SCCS/s."
	116	(file-name-nondirectory new)))
	117	(diff-internal-diff "sccs"
	118	(append '("diffs") diff-switches (list new))
	119	2)
	120	(error "%s does not exist"
	121	(concat (file-name-directory new) "SCCS/s."
	122	(file-name-nondirectory new)))))
	123
	124	(defun diff-rcs (new)
	125	"Find and display the differences between OLD and RCS files."
	126	(interactive
	127	(let (newf)
	128	(list
	129	(setq newf (buffer-file-name)
	130	newf (if (and newf (file-exists-p newf))
	131	(read-file-name
	132	(concat "Diff new file: ("
	133	(file-name-nondirectory newf) ") ")
	134	nil newf t)
	135	(read-file-name "Diff new file: " nil nil t))))))
	136
	137	(message "Comparing RCS file %s..." new)
	138	(let* ((fullname (expand-file-name new))
	139	(rcsfile (concat (file-name-directory fullname)
	140	"RCS/"
	141	(file-name-nondirectory fullname)
	142	diff-rcs-extension)))
	143	(if (file-exists-p rcsfile)
	144	(diff-internal-diff "rcsdiff" (append diff-switches (list fullname)) 4)
	145	(error "%s does not exist" rcsfile))))
	146
	147	(defun diff-internal-diff (diff-command sw strip)
	148	(let ((buffer-read-only nil))
b10a4379 JB	149	(with-output-to-temp-buffer "Diff Output"
	150	(buffer-disable-undo standard-output)
	151	(save-excursion
	152	(set-buffer standard-output)
	153	(erase-buffer)
aa228418	154	(apply 'call-process diff-command nil t nil sw)))
b10a4379 JB	155	(set-buffer "Diff Output")
	156	(goto-char (point-min))
	157	(while sw
	158	(if (string= (car sw) "-c")
	159	;; strip leading filenames from context diffs
	160	(progn (forward-line 2) (delete-region (point-min) (point))))
aa228418 JB	161	(if (and (string= (car sw) "-C") (string= "sccs" diff-command))
	162	;; strip stuff from SCCS context diffs
	163	(progn (forward-line 2) (delete-region (point-min) (point))))
	164	(setq sw (cdr sw)))
	165	(if strip
	166	;; strip stuff from SCCS context diffs
	167	(progn (forward-line strip) (delete-region (point-min) (point)))))
b10a4379 JB	168	(diff-mode)
	169	(if (string= "0" diff-total-differences)
	170	(let ((buffer-read-only nil))
	171	(insert (message "There are no differences.")))
	172	(narrow-to-region (point) (progn
	173	(forward-line 1)
	174	(if (re-search-forward diff-search-pattern
	175	nil t)
	176	(goto-char (match-beginning 0))
	177	(goto-char (point-max)))))
	178	(setq diff-current-difference "1")))
	179
aa228418	180	;; Take a buffer full of Unix diff output and go into a mode to easily
b10a4379 JB	181	;; see the next and previous difference
	182	(defun diff-mode ()
	183	"Diff Mode is used by \\[diff] for perusing the output from the diff program.
	184	All normal editing commands are turned off. Instead, these are available:
	185	\\<diff-mode-map>
	186	\\[diff-beginning-of-diff] Move point to start of this difference.
	187	\\[scroll-up] Scroll to next screen of this difference.
	188	\\[scroll-down] Scroll to previous screen of this difference.
	189	\\[diff-next-difference] Move to Next Difference.
	190	\\[diff-previous-difference] Move to Previous Difference.
	191	\\[diff-show-difference] Jump to difference specified by numeric position.
	192	"
	193	(interactive)
	194	(use-local-map diff-mode-map)
	195	(setq buffer-read-only t
	196	major-mode 'diff-mode
	197	mode-name "Diff"
	198	mode-line-modified "--- "
	199	mode-line-process
	200	'(" " diff-current-difference "/" diff-total-differences))
	201	(make-local-variable 'diff-current-difference)
	202	(set (make-local-variable 'diff-total-differences)
	203	(int-to-string (diff-count-differences))))
	204
	205	(defun diff-next-difference (n)
aa228418 JB	206	"Go to the beginning of the next difference.
aa228418 JB	207	Differences are delimited by `diff-search-pattern'."
b10a4379 JB	208	(interactive "p")
	209	(if (< n 0) (diff-previous-difference (- n))
	210	(if (zerop n) ()
	211	(goto-char (point-min))
	212	(forward-line 1) ; to get past the match for the start of this diff
	213	(widen)
	214	(if (re-search-forward diff-search-pattern nil 'move n)
	215	(let ((start (goto-char (match-beginning 0))))
	216	(forward-line 1)
	217	(if (re-search-forward diff-search-pattern nil 'move)
	218	(goto-char (match-beginning 0)))
	219	(narrow-to-region start (point))
	220	(setq diff-current-difference
	221	(int-to-string (+ n (string-to-int
	222	diff-current-difference)))))
	223	(re-search-backward diff-search-pattern nil)
	224	(narrow-to-region (point) (point-max))
	225	(message "No following differences.")
	226	(setq diff-current-difference diff-total-differences))
	227	(goto-char (point-min)))))
	228
	229	(defun diff-previous-difference (n)
aa228418 JB	230	"Go the the beginning of the previous difference.
aa228418 JB	231	Differences are delimited by `diff-search-pattern'."
b10a4379 JB	232	(interactive "p")
	233	(if (< n 0) (diff-next-difference (- n))
	234	(if (zerop n) ()
	235	(goto-char (point-min))
	236	(widen)
	237	(if (re-search-backward diff-search-pattern nil 'move n)
	238	(setq diff-current-difference
	239	(int-to-string (- (string-to-int diff-current-difference) n)))
	240	(message "No previous differences.")
	241	(setq diff-current-difference "1"))
	242	(narrow-to-region (point) (progn
	243	(forward-line 1)
	244	(re-search-forward diff-search-pattern nil)
	245	(goto-char (match-beginning 0))))
	246	(goto-char (point-min)))))
	247
	248	(defun diff-show-difference (n)
aa228418	249	"Show difference number N (prefix argument)."
b10a4379 JB	250	(interactive "p")
	251	(let ((cur (string-to-int diff-current-difference)))
	252	(cond ((or (= n cur)
	253	(zerop n)
	254	(not (natnump n))) ; should signal an error perhaps.
	255	;; just redisplay.
	256	(goto-char (point-min)))
	257	((< n cur)
	258	(diff-previous-difference (- cur n)))
	259	((> n cur)
	260	(diff-next-difference (- n cur))))))
	261
	262	(defun diff-beginning-of-diff ()
	263	"Go to beginning of current difference."
	264	(interactive)
	265	(goto-char (point-min)))
	266
	267	;; This function counts up the number of differences in the buffer.
	268	(defun diff-count-differences ()
	269	"Count number of differences in the current buffer."
	270	(message "Counting differences...")
	271	(save-excursion
	272	(save-restriction
	273	(widen)
	274	(goto-char (point-min))
	275	(let ((cnt 0))
	276	(while (re-search-forward diff-search-pattern nil t)
	277	(setq cnt (1+ cnt)))
	278	(message "Counting differences...done (%d)" cnt)
	279	cnt))))
c0274f38 ER	280
c0274f38 ER	281	;;; diff.el ends here