lisp/ediff-diff.el

   1 ;;; ediff-diff.el --- diff-related utilities
   2
   3 ;; Copyright (C) 1994, 1995 Free Software Foundation, Inc.
   4
   5 ;; Author: Michael Kifer <kifer@cs.sunysb.edu>
   6
   7 ;; This file is part of GNU Emacs.
   8
   9 ;; GNU Emacs is free software; you can redistribute it and/or modify
  10 ;; it under the terms of the GNU General Public License as published by
  11 ;; the Free Software Foundation; either version 2, or (at your option)
  12 ;; any later version.
  13
  14 ;; GNU Emacs is distributed in the hope that it will be useful,
  15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 ;; GNU General Public License for more details.
  18
  19 ;; You should have received a copy of the GNU General Public License
  20 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  21 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  22 ;; Boston, MA 02111-1307, USA.
  23
  24 ;;; Code:
  25
  26 (require 'ediff-init)
  27
  28
  29 (defvar ediff-shell
  30   (cond ((eq system-type 'emx) "cmd") ; OS/2
  31         ((eq system-type 'ms-dos) shell-file-name) ; no standard name on MS-DOS
  32         ((memq system-type '(vax-vms axp-vms)) "*dcl*") ; VMS
  33         (t  "sh")) ; UNIX
  34   "*The shell used to run diff and patch.  If user's .profile or
  35 .cshrc files are set up correctly, any shell will do.  However, some people
  36 set $prompt or other things incorrectly, which leads to undesirable output
  37 messages.  These may cause Ediff to fail.  In such a case, set ediff-shell
  38 to a shell that you are not using or, better, fix your shell's startup file.")
  39
  40
  41 (defvar ediff-diff-program "diff"
  42   "*Program to use for generating the differential of the two files.")
  43 (defvar ediff-diff-options ""
  44   "*Options to pass to `ediff-diff-program'.
  45 If diff\(1\) is used as `ediff-diff-program', then the most useful options are
  46 `-w', to ignore space, and `-i', to ignore case of letters.
  47 At present, the option `-c' is ignored, since Ediff doesn't understand this
  48 type of output.")
  49
  50 (defvar ediff-custom-diff-program ediff-diff-program
  51   "*Program to use for generating custom diff output for saving it in a file.
  52 This output is not used by Ediff internally.")
  53 (defvar ediff-custom-diff-options "-c"
  54   "*Options to pass to `ediff-custom-diff-program'.")
  55
  56 ;;; Support for diff3
  57
  58 (defvar ediff-match-diff3-line "^====\\(.?\\)$"
  59   "Pattern to match lines produced by diff3 that describe differences.")
  60 (defvar ediff-diff3-program "diff3"
  61   "*Program to be used for three-way comparison.
  62 Must produce output compatible with Unix's diff3 program.")
  63 (defvar ediff-diff3-options ""
  64   "*Options to pass to `ediff-diff3-program'.")
  65 (defvar ediff-diff3-ok-lines-regexp
  66   "^\\([1-3]:\\|====\\|  \\|.*Warning *:\\|.*No newline\\|.*missing newline\\)"
  67   "*Regexp that matches normal output lines from `ediff-diff3-program'.
  68 Lines that do not match are assumed to be error messages.")
  69
  70 ;; keeps the status of the current diff in 3-way jobs.
  71 ;; the status can be =diff(A), =diff(B), or =diff(A+B)
  72 (ediff-defvar-local ediff-diff-status "" "")
  73
  74 ;; Support for patch
  75
  76 (defvar ediff-patch-program "patch"
  77   "*Name of the program that applies patches.")
  78 (defvar ediff-patch-options ""
  79   "*Options to pass to ediff-patch-program.")
  80
  81 ;; The buffer of the patch file.
  82 (defvar ediff-patch-buf nil)
  83 ;; The buffer where patch would display its diagnostics.
  84 (defvar ediff-patch-diagnostics nil)
  85
  86
  87 ;;; Fine differences
  88
  89 (ediff-defvar-local ediff-auto-refine (if (ediff-has-face-support-p) 'on 'nix)
  90   "If `on', Ediff auto-highlights fine diffs for the current diff region.
  91 If `off', auto-highlighting is not used. If `nix', no fine diffs are shown
  92 at all, unless the user force-refines the region by hitting `*'.
  93
  94 This variable can be set either in .emacs or toggled interactively.
  95 Use `setq-default' if setting it in .emacs")
  96
  97 (ediff-defvar-local ediff-ignore-similar-regions nil
  98   "*If t, skip over difference regions that differ only in the white space and line breaks.
  99 This variable can be set either in .emacs or toggled interactively.
 100 Use `setq-default' if setting it in .emacs")
 101
 102 (ediff-defvar-local ediff-auto-refine-limit 700
 103   "Auto-refine only those regions that are smaller than this number of bytes.")
 104
 105 ;;; General
 106
 107 (defvar ediff-diff-ok-lines-regexp
 108   "^\\([0-9,]+[acd][0-9,]+$\\|[<>] \\|---\\|.*Warning *:\\|.*No newline\\|.*missing newline\\)"
 109   "Regexp that matches normal output lines from `ediff-diff-program'.
 110 This is mostly lifted from Emerge, except that Ediff also considers
 111 warnings and `Missing newline'-type messages to be normal output.
 112 Lines that do not match are assumed to be error messages.")
 113
 114 (defvar ediff-match-diff-line (let ((x "\\([0-9]+\\)\\(\\|,\\([0-9]+\\)\\)"))
 115                                 (concat "^" x "\\([acd]\\)" x "$"))
 116   "Pattern to match lines produced by diff that describe differences.")
 117
 118 (ediff-defvar-local ediff-setup-diff-regions-function nil
 119   "value is a function symbol depending on the kind of job is to be done.
 120 For 2-way jobs and for ediff-merge, it should be `ediff-setup-diff-regions'.
 121 For jobs requiring diff3, it should be `ediff-setup-diff-regions3'.
 122
 123 The function should take three mandatory arguments, file-A, file-B, and
 124 file-C. It may ignore file C for diff2 jobs. It should also take
 125 one optional arguments, diff-number to refine.")
 126
 127
 128 ;;; Functions
 129
 130 ;; Generate the difference vector and overlays for the two files
 131 ;; With optional arg REG-TO-REFINE, refine this region.
 132 ;; File-C argument is not used here. It is there just because
 133 ;; ediff-setup-diff-regions is called via a funcall to
 134 ;; ediff-setup-diff-regions-function, which can also have the value
 135 ;; ediff-setup-diff-regions3, which takes 4 arguments.
 136 (defun ediff-setup-diff-regions (file-A file-B file-C)
 137 ;;;  ;; Force all minibuffers to display ediff's messages.
 138 ;;;  ;; When xemacs implements minibufferless frames, this won't be necessary
 139 ;;;  (if ediff-xemacs-p (setq synchronize-minibuffers t))
 140
 141   (or (ediff-buffer-live-p ediff-diff-buffer)
 142       (setq ediff-diff-buffer
 143             (get-buffer-create (ediff-unique-buffer-name "*ediff-diff" "*"))))
 144
 145   (message "Computing differences ...")
 146   (ediff-exec-process ediff-diff-program ediff-diff-buffer 'synchronize
 147                       ediff-diff-options file-A file-B)
 148
 149   (ediff-prepare-error-list ediff-diff-ok-lines-regexp ediff-diff-buffer)
 150   ;;(message "Computing differences ... done")
 151   (ediff-convert-diffs-to-overlays
 152    (ediff-extract-diffs
 153     ediff-diff-buffer ediff-word-mode ediff-narrow-bounds)))
 154
 155 ;; If file-A/B/C is nil, do 2-way comparison with the non-nil buffers
 156 ;; This function works for diff3 and diff2 jobs
 157 (defun ediff-setup-fine-diff-regions (file-A file-B file-C reg-num)
 158   (or (ediff-buffer-live-p ediff-fine-diff-buffer)
 159       (setq ediff-fine-diff-buffer
 160             (get-buffer-create
 161              (ediff-unique-buffer-name "*ediff-fine-diff" "*"))))
 162
 163   (let (diff3-job diff-program ok-regexp diff-list)
 164     (setq diff3-job ediff-3way-job
 165           diff-program (if diff3-job ediff-diff3-program ediff-diff-program)
 166           ok-regexp (if diff3-job
 167                         ediff-diff3-ok-lines-regexp
 168                         ediff-diff-ok-lines-regexp))
 169
 170     (ediff-message-if-verbose "Refining difference region %d ..." (1+ reg-num))
 171     (ediff-exec-process diff-program ediff-fine-diff-buffer 'synchronize
 172                         ;; The shuffle below is because we can compare 3-way
 173                         ;; or in several 2-way fashions, like fA fC, fA fB,
 174                         ;; or fB fC.
 175                         (if file-A file-A file-B)
 176                         (if file-B file-B file-A)
 177                         (if diff3-job
 178                             (if file-C file-C file-B))
 179                         ) ; exec process
 180
 181     (ediff-prepare-error-list ok-regexp ediff-fine-diff-buffer)
 182     (ediff-message-if-verbose
 183      "")
 184     ;; "Refining difference region %d ... done" (1+ reg-num))
 185
 186     (setq diff-list
 187           (if diff3-job
 188               (ediff-extract-diffs3
 189                ediff-fine-diff-buffer '3way-comparison 'word-mode)
 190             (ediff-extract-diffs ediff-fine-diff-buffer 'word-mode)))
 191     ;; fixup diff-list
 192     (if diff3-job
 193         (cond ((not file-A)
 194                (mapcar (function (lambda (elt)
 195                                    (aset elt 0 nil)
 196                                    (aset elt 1 nil)))
 197                        (cdr diff-list)))
 198               ((not file-B)
 199                (mapcar (function (lambda (elt)
 200                                    (aset elt 2 nil)
 201                                    (aset elt 3 nil)))
 202                        (cdr diff-list)))
 203               ((not file-C)
 204                (mapcar (function (lambda (elt)
 205                                    (aset elt 4 nil)
 206                                    (aset elt 5 nil)))
 207                        (cdr diff-list)))
 208           ))
 209
 210     (ediff-convert-fine-diffs-to-overlays diff-list reg-num)
 211     ))
 212
 213
 214 (defun ediff-prepare-error-list (ok-regexp diff-buff)
 215   (or (ediff-buffer-live-p ediff-error-buffer)
 216       (setq ediff-error-buffer
 217             (get-buffer-create (ediff-unique-buffer-name
 218                                 "*ediff-errors" "*"))))
 219   (ediff-eval-in-buffer ediff-error-buffer
 220     (erase-buffer)
 221     (insert (ediff-eval-in-buffer diff-buff (buffer-string)))
 222     (goto-char (point-min))
 223     (delete-matching-lines ok-regexp)
 224     (if (memq system-type '(vax-vms axp-vms))
 225         (delete-matching-lines "^$")))
 226   ;; If diff reports errors, show them then quit.
 227   (if (/= 0 (ediff-eval-in-buffer ediff-error-buffer (buffer-size)))
 228       (let ((ctl-buf ediff-control-buffer)
 229             (error-buf ediff-error-buffer))
 230         (ediff-skip-unsuitable-frames)
 231         (switch-to-buffer error-buf)
 232         (ediff-kill-buffer-carefully ctl-buf)
 233         (error "Errors in diff output. Diff output is in %S" diff-buff))))
 234
 235 ;; BOUNDS specifies visibility bounds to use.
 236 ;; WORD-MODE tells whether we are in the word-mode or not.
 237 ;; If WORD-MODE, also construct vector of diffs using word numbers.
 238 ;; Else, use point values.
 239 ;; This function handles diff-2 jobs including the case of
 240 ;; merging buffers and files without ancestor.
 241 (defun ediff-extract-diffs (diff-buffer word-mode &optional bounds)
 242   (let ((A-buffer ediff-buffer-A)
 243         (B-buffer ediff-buffer-B)
 244         (C-buffer ediff-buffer-C)
 245         (a-prev 1) ; this is needed to set the first diff line correctly
 246         (b-prev 1)
 247         (c-prev 1)
 248         diff-list shift-A shift-B
 249         )
 250
 251     ;; diff list contains word numbers, unless changed later
 252     (setq diff-list (cons (if word-mode 'words 'points)
 253                           diff-list))
 254     ;; we don't use visibility bounds for buffer C when merging
 255     (if bounds
 256         (setq shift-A
 257               (ediff-overlay-start
 258                (ediff-get-value-according-to-buffer-type 'A bounds))
 259               shift-B
 260               (ediff-overlay-start
 261                (ediff-get-value-according-to-buffer-type 'B bounds))))
 262
 263     ;; reset point in buffers A/B/C
 264     (ediff-eval-in-buffer A-buffer
 265       (goto-char (if shift-A shift-A (point-min))))
 266     (ediff-eval-in-buffer B-buffer
 267       (goto-char (if shift-B shift-B (point-min))))
 268     (if (ediff-buffer-live-p C-buffer)
 269         (ediff-eval-in-buffer C-buffer
 270           (goto-char (point-min))))
 271
 272     (ediff-eval-in-buffer diff-buffer
 273       (goto-char (point-min))
 274       (while (re-search-forward ediff-match-diff-line nil t)
 275        (let* ((a-begin (string-to-int (buffer-substring (match-beginning 1)
 276                                                         (match-end 1))))
 277               (a-end  (let ((b (match-beginning 3))
 278                             (e (match-end 3)))
 279                         (if b
 280                             (string-to-int (buffer-substring b e))
 281                           a-begin)))
 282               (diff-type (buffer-substring (match-beginning 4) (match-end 4)))
 283               (b-begin (string-to-int (buffer-substring (match-beginning 5)
 284                                                         (match-end 5))))
 285               (b-end (let ((b (match-beginning 7))
 286                            (e (match-end 7)))
 287                        (if b
 288                            (string-to-int (buffer-substring b e))
 289                          b-begin)))
 290               a-begin-pt a-end-pt b-begin-pt b-end-pt
 291               c-begin c-end c-begin-pt c-end-pt)
 292          ;; fix the beginning and end numbers, because diff is somewhat
 293          ;; strange about how it numbers lines
 294          (if (string-equal diff-type "a")
 295              (setq b-end (1+ b-end)
 296                    a-begin (1+ a-begin)
 297                    a-end a-begin)
 298            (if (string-equal diff-type "d")
 299                (setq a-end (1+ a-end)
 300                      b-begin (1+ b-begin)
 301                      b-end b-begin)
 302              ;; (string-equal diff-type "c")
 303              (setq a-end (1+ a-end)
 304                    b-end (1+ b-end))))
 305
 306          (if (eq ediff-default-variant 'default-B)
 307              (setq c-begin b-begin
 308                    c-end b-end)
 309            (setq c-begin a-begin
 310                  c-end a-end))
 311
 312          ;; compute main diff vector
 313          (if word-mode
 314              ;; make diff-list contain word numbers
 315              (setq diff-list
 316                    (nconc diff-list
 317                           (list
 318                            (if (ediff-buffer-live-p C-buffer)
 319                                (vector (- a-begin a-prev) (- a-end a-begin)
 320                                        (- b-begin b-prev) (- b-end b-begin)
 321                                        (- c-begin c-prev) (- c-end c-begin)
 322                                        nil nil ; dummy ancestor
 323                                        nil     ; state of diff
 324                                        nil     ; state of merge
 325                                        nil     ; state of ancestor
 326                                        )
 327                              (vector (- a-begin a-prev) (- a-end a-begin)
 328                                      (- b-begin b-prev) (- b-end b-begin)
 329                                      nil nil ; dummy buf C
 330                                      nil nil ; dummy ancestor
 331                                      nil     ; state of diff
 332                                      nil     ; state of merge
 333                                      nil     ; state of ancestor
 334                                      ))
 335                            ))
 336                    a-prev a-end
 337                    b-prev b-end
 338                    c-prev c-end)
 339            ;; else convert lines to points
 340            (ediff-eval-in-buffer A-buffer
 341              (forward-line (- a-begin a-prev))
 342              (setq a-begin-pt (point))
 343              (forward-line (- a-end a-begin))
 344              (setq a-end-pt (point)
 345                    a-prev a-end))
 346            (ediff-eval-in-buffer B-buffer
 347              (forward-line (- b-begin b-prev))
 348              (setq b-begin-pt (point))
 349              (forward-line (- b-end b-begin))
 350              (setq b-end-pt (point)
 351                    b-prev b-end))
 352            (if (ediff-buffer-live-p C-buffer)
 353                (ediff-eval-in-buffer C-buffer
 354                  (forward-line (- c-begin c-prev))
 355                  (setq c-begin-pt (point))
 356                  (forward-line (- c-end c-begin))
 357                  (setq c-end-pt (point)
 358                        c-prev c-end)))
 359            (setq diff-list
 360                  (nconc
 361                   diff-list
 362                   (list
 363                    (if (ediff-buffer-live-p C-buffer)
 364                        (vector
 365                         a-begin-pt a-end-pt b-begin-pt b-end-pt
 366                         c-begin-pt c-end-pt
 367                         nil nil ; dummy ancestor
 368                         ;; state of diff
 369                         ;; shows which buff is different from the other two
 370                         (if (eq ediff-default-variant 'default-B) 'A 'B)
 371                         ediff-default-variant   ; state of merge
 372                         nil                     ; state of ancestor
 373                         )
 374                      (vector a-begin-pt a-end-pt
 375                              b-begin-pt b-end-pt
 376                              nil nil    ; dummy buf C
 377                              nil nil    ; dummy ancestor
 378                              nil nil    ; dummy state of diff & merge
 379                              nil        ; dummy state of ancestor
 380                              )))
 381                   )))
 382
 383          ))) ; end ediff-eval-in-buffer
 384     diff-list
 385     ))
 386
 387
 388 (defun ediff-convert-diffs-to-overlays (diff-list)
 389   (ediff-set-diff-overlays-in-one-buffer 'A diff-list)
 390   (ediff-set-diff-overlays-in-one-buffer 'B diff-list)
 391   (if ediff-3way-job
 392       (ediff-set-diff-overlays-in-one-buffer 'C diff-list))
 393   (if ediff-merge-with-ancestor-job
 394       (ediff-set-diff-overlays-in-one-buffer 'Ancestor diff-list))
 395   ;; set up vector showing the status of merge regions
 396   (if ediff-merge-job
 397       (setq ediff-state-of-merge
 398             (vconcat
 399              (mapcar (function
 400                       (lambda (elt)
 401                         (let ((state-of-merge (aref elt 9))
 402                               (state-of-ancestor (aref elt 10)))
 403                           (vector
 404                            (if state-of-merge (format "%S" state-of-merge))
 405                            state-of-ancestor))))
 406                      ;; the first elt designates type of list
 407                      (cdr diff-list))
 408              )))
 409   (message "Processing difference regions ... done"))
 410
 411
 412 (defun ediff-set-diff-overlays-in-one-buffer (buf-type diff-list)
 413   (let* ((current-diff -1)
 414          (buff (ediff-get-buffer buf-type))
 415          ;; ediff-extract-diffs puts the type of diff-list as the first elt
 416          ;; of this list. The type is either 'points or 'words
 417          (diff-list-type (car diff-list))
 418          (shift (ediff-overlay-start
 419                  (ediff-get-value-according-to-buffer-type
 420                   buf-type ediff-narrow-bounds)))
 421          (limit (ediff-overlay-end
 422                  (ediff-get-value-according-to-buffer-type
 423                   buf-type ediff-narrow-bounds)))
 424          diff-overlay-list list-element total-diffs
 425          begin end pt-saved overlay state-of-diff)
 426
 427     (setq diff-list (cdr diff-list)) ; discard diff list type
 428     (setq total-diffs (length diff-list))
 429
 430     ;; shift, if necessary
 431     (ediff-eval-in-buffer buff (setq pt-saved shift))
 432
 433     (while diff-list
 434       (setq current-diff (1+ current-diff)
 435             list-element (car diff-list)
 436             begin        (aref list-element (cond ((eq buf-type 'A) 0)
 437                                                   ((eq buf-type 'B) 2)
 438                                                   ((eq buf-type 'C) 4)
 439                                                   (t 6)))  ; Ancestor
 440             end          (aref list-element (cond ((eq buf-type 'A) 1)
 441                                                   ((eq buf-type 'B) 3)
 442                                                   ((eq buf-type 'C) 5)
 443                                                   (t 7)))  ; Ancestor
 444             state-of-diff (aref list-element 8)
 445             )
 446
 447       (cond ((and (not (eq buf-type state-of-diff))
 448                   (not (eq buf-type 'Ancestor))
 449                   (memq state-of-diff '(A B C)))
 450              (setq state-of-diff
 451                    (car (delq buf-type (delq state-of-diff (list 'A 'B 'C)))))
 452              (setq state-of-diff (format "=diff(%S)" state-of-diff))
 453              )
 454             (t (setq state-of-diff nil)))
 455
 456       ;; Put overlays at appropriate places in buffer
 457       ;; convert word numbers to points, if necessary
 458       (if (eq diff-list-type 'words)
 459           (progn
 460             (ediff-eval-in-buffer buff (goto-char pt-saved))
 461             (setq begin (ediff-goto-word (1+ begin) buff)
 462                   end (ediff-goto-word end buff 'end))
 463             (if (> end limit) (setq end limit))
 464             (if (> begin end) (setq begin end))
 465             (setq pt-saved (ediff-eval-in-buffer buff (point)))))
 466       (setq overlay (ediff-make-bullet-proof-overlay begin end buff))
 467
 468       (ediff-overlay-put overlay 'priority ediff-shadow-overlay-priority)
 469       (ediff-overlay-put overlay 'ediff-diff-num current-diff)
 470       (if (and (ediff-has-face-support-p)
 471                ediff-use-faces ediff-highlight-all-diffs)
 472           (ediff-set-overlay-face
 473            overlay (ediff-background-face buf-type current-diff)))
 474
 475       (if (= 0 (mod current-diff 10))
 476           (message "Buffer %S: Processing difference region %d of %d"
 477                    buf-type current-diff total-diffs))
 478       ;; record all overlays for this difference
 479       ;; the second elt, nil, is a place holder for the fine diff vector.
 480       ;; the third elt, nil, is a place holder for no-fine-diffs flag.
 481       (setq diff-overlay-list
 482             (nconc
 483              diff-overlay-list
 484              (list (vector overlay nil nil state-of-diff)))
 485             diff-list
 486             (cdr diff-list))
 487       ) ; while
 488
 489     (set (intern (format "ediff-difference-vector-%S" buf-type))
 490          (vconcat diff-overlay-list))
 491     ))
 492
 493 ;; `n' is the diff region to work on.  Default is ediff-current-difference.
 494 ;; if `flag' is 'noforce then make fine-diffs only if this region's fine
 495 ;; diffs have not been computed before.
 496 ;; if `flag' is 'skip then don't compute fine diffs for this region.
 497 (defun ediff-make-fine-diffs (&optional n flag)
 498   (or n  (setq n ediff-current-difference))
 499
 500   (if (< ediff-number-of-differences 1)
 501       (error "Sorry, it is not my job to munch identical variants..."))
 502
 503   (if ediff-word-mode
 504       (setq flag 'skip
 505             ediff-auto-refine 'nix))
 506
 507   (or (< n 0)
 508       (>= n ediff-number-of-differences)
 509       ;; n is within the range
 510       (let ((tmp-buffer (get-buffer-create ediff-tmp-buffer))
 511             (file-A ediff-temp-file-A)
 512             (file-B ediff-temp-file-B)
 513             (file-C ediff-temp-file-C)
 514             (empty-A (ediff-empty-diff-region-p n 'A))
 515             (empty-B (ediff-empty-diff-region-p n 'B))
 516             (empty-C (ediff-empty-diff-region-p n 'C))
 517             (whitespace-A (ediff-whitespace-diff-region-p n 'A))
 518             (whitespace-B (ediff-whitespace-diff-region-p n 'B))
 519             (whitespace-C (ediff-whitespace-diff-region-p n 'C))
 520             cumulative-fine-diff-length)
 521
 522         (cond ((and (eq flag 'noforce) (ediff-get-fine-diff-vector n 'A))
 523                ;; don't compute fine diffs if diff vector exists
 524                (if (ediff-no-fine-diffs-p n)
 525                    (ediff-message-if-verbose
 526                     "Only white-space differences in region %d" (1+ n))))
 527               ;; If one of the regions is empty (or 2 in 3way comparison)
 528               ;; then don't refine.
 529               ;; If the region happens to be entirely whitespace or empty then
 530               ;; mark as such.
 531               ((> (length (delq nil (list empty-A empty-B empty-C))) 1)
 532                (if (and (ediff-looks-like-combined-merge n)
 533                         ediff-merge-job)
 534                    (ediff-set-fine-overlays-in-one-buffer 'C nil n))
 535                (if ediff-3way-comparison-job
 536                    (ediff-message-if-verbose
 537                     "Region %d is empty in all buffers but %S"
 538                     (1+ n)
 539                     (cond ((not empty-A) 'A)
 540                           ((not empty-B) 'B)
 541                           ((not empty-C) 'C)))
 542                  (ediff-message-if-verbose
 543                   "Region %d in buffer %S is empty"
 544                   (1+ n)
 545                   (cond (empty-A 'A)
 546                         (empty-B 'B)
 547                         (empty-C 'C)))
 548                  )
 549                ;; if all regions happen to be whitespace, indicate this
 550                (if (and whitespace-A whitespace-B whitespace-C)
 551                    (ediff-mark-diff-as-space-only n t)
 552                  (ediff-mark-diff-as-space-only n nil)))
 553               ;; don't compute fine diffs for this region
 554               ((eq flag 'skip)
 555                (or (ediff-get-fine-diff-vector n 'A)
 556                    (memq ediff-auto-refine '(off nix))
 557                    (ediff-message-if-verbose
 558                     "Region %d exceeds auto-refine limit. `%s' force-refines"
 559                     (1+ n)
 560                     (substitute-command-keys
 561                      "\\[ediff-make-or-kill-fine-diffs]")
 562                     )))
 563               (t
 564                ;; recompute fine diffs
 565                (ediff-wordify
 566                 (ediff-get-diff-posn 'A 'beg n)
 567                 (ediff-get-diff-posn 'A 'end n)
 568                 ediff-buffer-A
 569                 tmp-buffer
 570                 ediff-control-buffer)
 571                (setq file-A
 572                      (ediff-make-temp-file tmp-buffer "fineDiffA" file-A))
 573
 574                (ediff-wordify
 575                 (ediff-get-diff-posn 'B 'beg n)
 576                 (ediff-get-diff-posn 'B 'end n)
 577                 ediff-buffer-B
 578                 tmp-buffer
 579                 ediff-control-buffer)
 580                (setq file-B
 581                      (ediff-make-temp-file tmp-buffer "fineDiffB" file-B))
 582
 583                (if ediff-3way-job
 584                    (progn
 585                      (ediff-wordify
 586                       (ediff-get-diff-posn 'C 'beg n)
 587                       (ediff-get-diff-posn 'C 'end n)
 588                       ediff-buffer-C
 589                       tmp-buffer
 590                       ediff-control-buffer)
 591                      (setq file-C
 592                            (ediff-make-temp-file
 593                             tmp-buffer "fineDiffC" file-C))))
 594
 595                ;; save temp file names.
 596                (setq ediff-temp-file-A file-A
 597                      ediff-temp-file-B file-B
 598                      ediff-temp-file-C file-C)
 599
 600                ;; set the new vector of fine diffs, if none exists
 601                (cond ((and ediff-3way-job whitespace-A)
 602                       (ediff-setup-fine-diff-regions nil file-B file-C n))
 603                      ((and ediff-3way-job whitespace-B)
 604                       (ediff-setup-fine-diff-regions file-A nil file-C n))
 605                      ((and ediff-3way-job
 606                            (or whitespace-C
 607                                (and ediff-merge-job
 608                                     (ediff-looks-like-combined-merge n))))
 609                       (ediff-setup-fine-diff-regions file-A file-B nil n))
 610                      (t
 611                       (ediff-setup-fine-diff-regions file-A file-B file-C n)))
 612
 613                (setq cumulative-fine-diff-length
 614                      (+ (length (ediff-get-fine-diff-vector n 'A))
 615                                    (length (ediff-get-fine-diff-vector n 'B))
 616                                    (if file-C
 617                                        (length
 618                                         (ediff-get-fine-diff-vector n 'C))
 619                                      0)))
 620
 621                (cond ((or
 622                        ;; all regions are white space
 623                        (and whitespace-A whitespace-B whitespace-C)
 624                        ;; none is white space and no fine diffs detected
 625                        (and (not whitespace-A)
 626                             (not whitespace-B)
 627                             (not (and ediff-3way-job whitespace-C))
 628                             (eq cumulative-fine-diff-length 0)))
 629                       (ediff-mark-diff-as-space-only n t)
 630                       (ediff-message-if-verbose
 631                        "Only white-space differences in region %d" (1+ n)))
 632                      ((eq cumulative-fine-diff-length 0)
 633                       (ediff-mark-diff-as-space-only n nil)
 634                       (ediff-message-if-verbose
 635                        "Only white-space differences in region %d %s"
 636                        (1+ n)
 637                        (cond (whitespace-A "in buffers B & C")
 638                              (whitespace-B "in buffers A & C")
 639                              (whitespace-C "in buffers A & B"))))
 640                      (t
 641                       (ediff-mark-diff-as-space-only n nil)))
 642                )
 643               ) ; end cond
 644         (ediff-set-fine-diff-properties n)
 645         )))
 646
 647 ;; Interface to ediff-make-fine-diffs. Checks for auto-refine limit, etc.
 648 (defun ediff-install-fine-diff-if-necessary (n)
 649   (cond ((eq ediff-auto-refine 'on)
 650          (if (and
 651               (> ediff-auto-refine-limit
 652                  (- (ediff-get-diff-posn 'A 'end n)
 653                     (ediff-get-diff-posn 'A 'beg n)))
 654               (> ediff-auto-refine-limit
 655                  (- (ediff-get-diff-posn 'B 'end n)
 656                     (ediff-get-diff-posn 'B 'beg n))))
 657              (ediff-make-fine-diffs n 'noforce)
 658            (ediff-make-fine-diffs n 'skip)))
 659
 660         ;; highlight iff fine diffs already exist
 661         ((eq ediff-auto-refine 'off)
 662          (ediff-make-fine-diffs n 'skip))))
 663
 664
 665 ;; if fine diff vector is not set for diff N, then do nothing
 666 (defun ediff-set-fine-diff-properties (n &optional default)
 667   (or (not (ediff-has-face-support-p))
 668       (< n 0)
 669       (>= n ediff-number-of-differences)
 670       ;; when faces are supported, set faces and priorities of fine overlays
 671       (progn
 672         (ediff-set-fine-diff-properties-in-one-buffer 'A n default)
 673         (ediff-set-fine-diff-properties-in-one-buffer 'B n default)
 674         (if ediff-3way-job
 675             (ediff-set-fine-diff-properties-in-one-buffer 'C n default)))))
 676
 677 (defun ediff-set-fine-diff-properties-in-one-buffer (buf-type
 678                                                      n &optional default)
 679   (let ((fine-diff-vector  (ediff-get-fine-diff-vector n buf-type))
 680         (face (if default
 681                   'default
 682                 (face-name
 683                  (intern (format "ediff-fine-diff-face-%S" buf-type)))))
 684         (priority (if default
 685                       0
 686                     (1+ (or (ediff-overlay-get
 687                              (symbol-value
 688                               (intern
 689                                (format
 690                                 "ediff-current-diff-overlay-%S" buf-type)))
 691                              'priority)
 692                             0)))))
 693     (mapcar
 694      (function (lambda (overl)
 695                  (ediff-set-overlay-face overl face)
 696                  (ediff-overlay-put overl 'priority priority)))
 697      fine-diff-vector)))
 698
 699 ;; This assumes buffer C and that the region looks like a combination of
 700 ;; regions in buffer A and C.
 701 (defun ediff-set-fine-overlays-for-combined-merge (diff-list reg-num)
 702   (let (overlay1 overlay2 overlay3)
 703     (setq overlay1 (ediff-make-bullet-proof-overlay (nth 0 diff-list)
 704                                                     (nth 1 diff-list)
 705                                                     ediff-buffer-C)
 706           overlay2 (ediff-make-bullet-proof-overlay (nth 2 diff-list)
 707                                                     (nth 3 diff-list)
 708                                                     ediff-buffer-C)
 709           overlay3 (ediff-make-bullet-proof-overlay (nth 4 diff-list)
 710                                                     (nth 5 diff-list)
 711                                                     ediff-buffer-C))
 712     (ediff-set-fine-diff-vector reg-num 'C (vector overlay1 overlay2 overlay3))
 713     ))
 714
 715
 716 ;; Convert diff list to overlays for a given DIFF-REGION
 717 ;; in buffer of type BUF-TYPE
 718 (defun ediff-set-fine-overlays-in-one-buffer (buf-type diff-list region-num)
 719   (let* ((current-diff -1)
 720          (reg-start (ediff-get-diff-posn buf-type 'beg region-num))
 721          (buff (ediff-get-buffer buf-type))
 722          combined-merge-diff-list
 723          diff-overlay-list list-element
 724          begin end overlay)
 725
 726     (ediff-clear-fine-differences-in-one-buffer region-num buf-type)
 727     (setq diff-list (cdr diff-list)) ; discard list type (words or points)
 728     (ediff-eval-in-buffer buff (goto-char reg-start))
 729
 730     ;; if it is a combined merge then set overlays in buff C specially
 731     (if (and ediff-merge-job (eq buf-type 'C)
 732              (setq combined-merge-diff-list
 733                    (ediff-looks-like-combined-merge region-num)))
 734         (ediff-set-fine-overlays-for-combined-merge
 735          combined-merge-diff-list region-num)
 736       ;; regular fine diff
 737       (while diff-list
 738         (setq current-diff (1+ current-diff)
 739               list-element (car diff-list)
 740               begin      (aref list-element (cond ((eq buf-type 'A) 0)
 741                                                   ((eq buf-type 'B) 2)
 742                                                   (t 4)))  ; buf C
 743               end        (aref list-element (cond ((eq buf-type 'A) 1)
 744                                                   ((eq buf-type 'B) 3)
 745                                                   (t 5)))) ; buf C
 746         (if (not (or begin end))
 747             () ; skip this diff
 748           ;; Put overlays at appropriate places in buffers
 749           ;; convert lines to points, if necessary
 750           (setq begin (ediff-goto-word (1+ begin) buff)
 751                 end (ediff-goto-word end buff 'end))
 752           (setq overlay (ediff-make-bullet-proof-overlay begin end buff))
 753           ;; record all overlays for this difference region
 754           (setq diff-overlay-list (nconc diff-overlay-list (list overlay))))
 755
 756         (setq diff-list (cdr diff-list))
 757         ) ; while
 758       ;; convert the list of difference information into a vector
 759       ;; for fast access
 760       (ediff-set-fine-diff-vector
 761        region-num buf-type (vconcat diff-overlay-list))
 762       )))
 763
 764
 765 ;; Stolen from emerge.el
 766 (defun ediff-get-diff3-group (file)
 767   ;; This save-excursion allows ediff-get-diff3-group to be called for the
 768   ;; various groups of lines (1, 2, 3) in any order, and for the lines to
 769   ;; appear in any order.  The reason this is necessary is that Gnu diff3
 770   ;; can produce the groups in the order 1, 2, 3 or 1, 3, 2.
 771   (save-excursion
 772     (re-search-forward
 773      (concat "^" file ":\\([0-9]+\\)\\(,\\([0-9]+\\)\\)?\\([ac]\\)$"))
 774     (beginning-of-line 2)
 775     ;; treatment depends on whether it is an "a" group or a "c" group
 776     (if (string-equal (buffer-substring (match-beginning 4) (match-end 4)) "c")
 777         ;; it is a "c" group
 778         (if (match-beginning 2)
 779             ;; it has two numbers
 780             (list (string-to-int
 781                    (buffer-substring (match-beginning 1) (match-end 1)))
 782                   (1+ (string-to-int
 783                        (buffer-substring (match-beginning 3) (match-end 3)))))
 784           ;; it has one number
 785           (let ((x (string-to-int
 786                     (buffer-substring (match-beginning 1) (match-end 1)))))
 787             (list x (1+ x))))
 788       ;; it is an "a" group
 789       (let ((x (1+ (string-to-int
 790                     (buffer-substring (match-beginning 1) (match-end 1))))))
 791         (list x x)))))
 792
 793
 794 ;; If WORD-MODE, construct vector of diffs using word numbers.
 795 ;; Else, use point values.
 796 ;; WORD-MODE also tells if we are in the word-mode or not.
 797 ;; If THREE-WAY-COMP, then it is a 3-way comparison. Else, it is merging
 798 ;; with ancestor, in which case buffer-C contents is identical to buffer-A/B,
 799 ;; contents (unless buffer-A is narrowed) depending on ediff-default-variant's
 800 ;; value.
 801 ;; BOUNDS specifies visibility bounds to use.
 802 (defun ediff-extract-diffs3 (diff-buffer word-mode three-way-comp
 803                                           &optional bounds)
 804   (let ((A-buffer ediff-buffer-A)
 805         (B-buffer ediff-buffer-B)
 806         (C-buffer ediff-buffer-C)
 807         (anc-buffer ediff-ancestor-buffer)
 808         (a-prev 1) ; needed to set the first diff line correctly
 809         (b-prev 1)
 810         (c-prev 1)
 811         (anc-prev 1)
 812         diff-list shift-A shift-B shift-C
 813         )
 814
 815     ;; diff list contains word numbers or points, depending on word-mode
 816     (setq diff-list (cons (if word-mode 'words 'points)
 817                           diff-list))
 818     (if bounds
 819         (setq shift-A
 820               (ediff-overlay-start
 821                (ediff-get-value-according-to-buffer-type 'A bounds))
 822               shift-B
 823               (ediff-overlay-start
 824                (ediff-get-value-according-to-buffer-type 'B bounds))
 825               shift-C
 826               (if three-way-comp
 827                   (ediff-overlay-start
 828                    (ediff-get-value-according-to-buffer-type 'C bounds)))))
 829
 830     ;; reset point in buffers A, B, C
 831     (ediff-eval-in-buffer A-buffer
 832       (goto-char (if shift-A shift-A (point-min))))
 833     (ediff-eval-in-buffer B-buffer
 834       (goto-char (if shift-B shift-B (point-min))))
 835     (if three-way-comp
 836         (ediff-eval-in-buffer C-buffer
 837           (goto-char (if shift-C shift-C (point-min)))))
 838     (if (ediff-buffer-live-p anc-buffer)
 839         (ediff-eval-in-buffer anc-buffer
 840           (goto-char (point-min))))
 841
 842     (ediff-eval-in-buffer diff-buffer
 843       (goto-char (point-min))
 844       (while (re-search-forward ediff-match-diff3-line nil t)
 845         ;; leave point after matched line
 846        (beginning-of-line 2)
 847        (let ((agreement (buffer-substring (match-beginning 1) (match-end 1))))
 848          ;; if the A and B files are the same and not 3way-comparison,
 849          ;; ignore the difference
 850          (if (or three-way-comp (not (string-equal agreement "3")))
 851              (let* ((a-begin (car (ediff-get-diff3-group "1")))
 852                     (a-end  (nth 1 (ediff-get-diff3-group "1")))
 853                     (b-begin (car (ediff-get-diff3-group "2")))
 854                     (b-end (nth 1 (ediff-get-diff3-group "2")))
 855                     (c-or-anc-begin (car (ediff-get-diff3-group "3")))
 856                     (c-or-anc-end (nth 1 (ediff-get-diff3-group "3")))
 857                     (state-of-merge
 858                      (cond ((string-equal agreement "1") 'prefer-A)
 859                            ((string-equal agreement "2") 'prefer-B)
 860                            (t ediff-default-variant)))
 861                     (state-of-diff-merge
 862                      (if (memq state-of-merge '(default-A prefer-A)) 'B 'A))
 863                     (state-of-diff-comparison
 864                      (cond ((string-equal agreement "1") 'A)
 865                            ((string-equal agreement "2") 'B)
 866                            ((string-equal agreement "3") 'C)))
 867                     state-of-ancestor
 868                     c-begin c-end
 869                     a-begin-pt a-end-pt
 870                     b-begin-pt b-end-pt
 871                     c-begin-pt c-end-pt
 872                     anc-begin-pt anc-end-pt)
 873
 874                (setq state-of-ancestor
 875                      (= c-or-anc-begin c-or-anc-end))
 876
 877                (cond (three-way-comp
 878                       (setq c-begin c-or-anc-begin
 879                             c-end c-or-anc-end))
 880                      ((eq ediff-default-variant 'default-B)
 881                       (setq c-begin b-begin
 882                             c-end b-end))
 883                      (t
 884                       (setq c-begin a-begin
 885                             c-end a-end)))
 886
 887                ;; compute main diff vector
 888                (if word-mode
 889                    ;; make diff-list contain word numbers
 890                    (setq diff-list
 891                          (nconc diff-list
 892                                 (list (vector
 893                                        (- a-begin a-prev) (- a-end a-begin)
 894                                        (- b-begin b-prev) (- b-end b-begin)
 895                                        (- c-begin c-prev) (- c-end c-begin)
 896                                        nil nil ; dummy ancestor
 897                                        nil     ; state of diff
 898                                        nil     ; state of merge
 899                                        nil     ; state of ancestor
 900                                        )))
 901                          a-prev a-end
 902                          b-prev b-end
 903                          c-prev c-end)
 904                  ;; else convert lines to points
 905                  (ediff-eval-in-buffer A-buffer
 906                    (forward-line (- a-begin a-prev))
 907                    (setq a-begin-pt (point))
 908                    (forward-line (- a-end a-begin))
 909                    (setq a-end-pt (point)
 910                          a-prev a-end))
 911                  (ediff-eval-in-buffer B-buffer
 912                    (forward-line (- b-begin b-prev))
 913                    (setq b-begin-pt (point))
 914                    (forward-line (- b-end b-begin))
 915                    (setq b-end-pt (point)
 916                          b-prev b-end))
 917                  (ediff-eval-in-buffer C-buffer
 918                    (forward-line (- c-begin c-prev))
 919                    (setq c-begin-pt (point))
 920                    (forward-line (- c-end c-begin))
 921                    (setq c-end-pt (point)
 922                          c-prev c-end))
 923                  (if (ediff-buffer-live-p anc-buffer)
 924                      (ediff-eval-in-buffer anc-buffer
 925                        (forward-line (- c-or-anc-begin anc-prev))
 926                        (setq anc-begin-pt (point))
 927                        (forward-line (- c-or-anc-end c-or-anc-begin))
 928                        (setq anc-end-pt (point)
 929                              anc-prev c-or-anc-end)))
 930                  (setq diff-list
 931                        (nconc
 932                         diff-list
 933                         ;; if comparing with ancestor, then there also is a
 934                         ;; state-of-difference marker
 935                         (if three-way-comp
 936                             (list (vector
 937                                    a-begin-pt a-end-pt
 938                                    b-begin-pt b-end-pt
 939                                    c-begin-pt c-end-pt
 940                                    nil nil ; ancestor begin/end
 941                                    state-of-diff-comparison
 942                                    nil  ; state of merge
 943                                    nil  ; state of ancestor
 944                                    ))
 945                           (list (vector a-begin-pt a-end-pt
 946                                         b-begin-pt b-end-pt
 947                                         c-begin-pt c-end-pt
 948                                         anc-begin-pt anc-end-pt
 949                                         state-of-diff-merge
 950                                         state-of-merge
 951                                         state-of-ancestor
 952                                         )))
 953                         )))
 954                ))
 955
 956          ))) ; end ediff-eval-in-buffer
 957     diff-list
 958     ))
 959
 960 ;; Generate the difference vector and overlays for three files
 961 ;; File-C is either the third file to compare (in case of 3-way comparison)
 962 ;; or it is the ancestor file.
 963 (defun ediff-setup-diff-regions3 (file-A file-B file-C)
 964
 965 ;;;  ;; force all minibuffers to display ediff's messages.
 966 ;;;  ;; when xemacs implements minibufferless frames, this won't be necessary
 967 ;;;  (if ediff-xemacs-p (setq synchronize-minibuffers t))
 968
 969   (or (ediff-buffer-live-p ediff-diff-buffer)
 970       (setq ediff-diff-buffer
 971             (get-buffer-create (ediff-unique-buffer-name "*ediff-diff" "*"))))
 972
 973   (message "Computing differences ...")
 974   (ediff-exec-process ediff-diff3-program ediff-diff-buffer 'synchronize
 975                       ediff-diff3-options file-A file-B file-C)
 976
 977   (ediff-prepare-error-list ediff-diff3-ok-lines-regexp ediff-diff-buffer)
 978   ;;(message "Computing differences ... done")
 979   (ediff-convert-diffs-to-overlays
 980    (ediff-extract-diffs3
 981     ediff-diff-buffer
 982     ediff-word-mode ediff-3way-comparison-job ediff-narrow-bounds)
 983    ))
 984
 985
 986 ;; Execute PROGRAM asynchronously, unless OS/2, Windows-*, or DOS, or unless
 987 ;; SYNCH is non-nil.  BUFFER must be a buffer object, and must be alive.  All
 988 ;; arguments in ARGS must be strings. The first arg may be a blank string, in
 989 ;; which case we delete it from ARGS list. We also delete nil from args.
 990 (defun ediff-exec-process (program buffer synch &rest args)
 991   (let ((data (match-data)))
 992     (if (string-match "^[ \t]*$" (car args)) ; delete blank string
 993         (setq args (cdr args)))
 994     (setq args (delq nil args)) ; delete nil from arguments
 995     (setq args (ediff-split-string (mapconcat 'identity args " ")))
 996     (unwind-protect
 997         (let ((directory default-directory)
 998               proc)
 999           (save-excursion
1000             (set-buffer buffer)
1001             (erase-buffer)
1002             (setq default-directory directory)
1003             (if (or (memq system-type '(emx ms-dos windows-nt windows-95))
1004                     synch)
1005                 ;; In OS/2 (emx) do it synchronously, since OS/2 doesn't let us
1006                 ;; delete files used by other processes. Thus, in ediff-buffers
1007                 ;; and similar functions, we can't delete temp files because
1008                 ;; they might be used by the asynch process that computes
1009                 ;; custom diffs. So, we have to wait till custom diff
1010                 ;; subprocess is done.
1011                 ;; Similarly for Windows-*
1012                 ;; In DOS, must synchronize because DOS doesn't have
1013                 ;; asynchronous processes.
1014                 (apply 'call-process program nil buffer nil args)
1015               ;; On other systems, do it asynchronously.
1016               (setq proc (get-buffer-process buffer))
1017               (if proc (kill-process proc))
1018               (setq proc
1019                     (apply 'start-process "Custom Diff" buffer program args))
1020               (setq mode-line-process '(":%s"))
1021               (set-process-sentinel proc 'ediff-process-sentinel)
1022               (set-process-filter proc 'ediff-process-filter)
1023               )))
1024       (store-match-data data))))
1025
1026 ;; This is shell-command-filter from simple.el in FSF Emacs.
1027 ;; Copied here because XEmacs doesn't have it.
1028 (defun ediff-process-filter (proc string)
1029   ;; Do save-excursion by hand so that we can leave point numerically unchanged
1030   ;; despite an insertion immediately after it.
1031   (let* ((obuf (current-buffer))
1032          (buffer (process-buffer proc))
1033          opoint
1034          (window (get-buffer-window buffer))
1035          (pos (window-start window)))
1036     (unwind-protect
1037         (progn
1038           (set-buffer buffer)
1039           (or (= (point) (point-max))
1040               (setq opoint (point)))
1041           (goto-char (point-max))
1042           (insert-before-markers string))
1043       ;; insert-before-markers moved this marker: set it back.
1044       (set-window-start window pos)
1045       ;; Finish our save-excursion.
1046       (if opoint
1047           (goto-char opoint))
1048       (set-buffer obuf))))
1049
1050 ;; like shell-command-sentinel but doesn't print an exit status message
1051 ;; we do this because diff always exits with status 1, if diffs are found
1052 ;; so shell-command-sentinel displays a confusing message to the user
1053 (defun ediff-process-sentinel (process signal)
1054   (if (and (memq (process-status process) '(exit signal))
1055            (buffer-name (process-buffer process)))
1056       (progn
1057         (save-excursion
1058           (set-buffer (process-buffer process))
1059           (setq mode-line-process nil))
1060         (delete-process process))))
1061
1062
1063 ;;; Word functions used to refine the current diff
1064
1065 (defvar ediff-forward-word-function 'ediff-forward-word
1066   "*Function to call to move to the next word.
1067 Used for splitting difference regions into individual words.")
1068
1069 (defvar ediff-whitespace " \n\t\f"
1070   "*Characters constituting white space.
1071 These characters are ignored when differing regions are split into words.")
1072
1073 ;;(defvar ediff-word-1 "a-zA-Z---_`'.?!:"
1074 (defvar ediff-word-1 "a-zA-Z---_"
1075   "*Characters that constitute words of type 1.
1076 More precisely, [ediff-word-1] is a regexp that matches type 1 words.
1077 See `ediff-forward-word' for more details.")
1078
1079 (defvar ediff-word-2 "0-9.,"
1080   "*Characters that constitute words of type 2.
1081 More precisely, [ediff-word-2] is a regexp that matches type 2 words.
1082 See `ediff-forward-word' for more details.")
1083
1084 (defvar ediff-word-3 "`'?!:;\"{}[]()"
1085   "*Characters that constitute words of type 3.
1086 More precisely, [ediff-word-3] is a regexp that matches type 3 words.
1087 See `ediff-forward-word' for more details.")
1088
1089 (defvar ediff-word-4
1090   (concat "^" ediff-word-1 ediff-word-2 ediff-word-3 ediff-whitespace)
1091   "*Characters that constitute words of type 4.
1092 More precisely, [ediff-word-4] is a regexp that matches type 4 words.
1093 See `ediff-forward-word' for more details.")
1094
1095 ;; Split region along word boundaries. Each word will be on its own line.
1096 ;; Output to buffer out-buffer.
1097 (defun ediff-forward-word ()
1098   "Move point one word forward.
1099 There are four types of words, each of which consists entirely of
1100 characters in `ediff-word-1', `ediff-word-2', `ediff-word-3', or
1101 `ediff-word-4'.  Words are recognized by passing these in turn as the
1102 argument to `skip-chars-forward'."
1103   (or (> (skip-chars-forward ediff-word-1) 0)
1104       (> (skip-chars-forward ediff-word-2) 0)
1105       (> (skip-chars-forward ediff-word-3) 0)
1106       (> (skip-chars-forward ediff-word-4) 0)
1107       ))
1108
1109 (defun ediff-wordify (beg end in-buffer out-buffer &optional control-buf)
1110   (let (sv-point string)
1111     (save-excursion
1112      (set-buffer in-buffer)
1113      (setq string (buffer-substring beg end))
1114
1115      (set-buffer out-buffer)
1116      (erase-buffer)
1117      (insert string)
1118      (goto-char (point-min))
1119      (skip-chars-forward ediff-whitespace)
1120      (delete-region (point-min) (point))
1121
1122      (while (not (eobp))
1123        ;; eval incontrol buf to let user create local versions for
1124        ;; different invocations
1125        (if control-buf
1126            (funcall
1127             (ediff-eval-in-buffer control-buf ediff-forward-word-function))
1128          (funcall ediff-forward-word-function))
1129        (setq sv-point (point))
1130        (skip-chars-forward ediff-whitespace)
1131        (delete-region sv-point (point))
1132        (insert "\n")))))
1133
1134 ;; copy string from BEG END from IN-BUF to OUT-BUF
1135 (defun ediff-copy-to-buffer (beg end in-buffer out-buffer)
1136   (let (string)
1137     (save-excursion
1138       (set-buffer in-buffer)
1139      (setq string (buffer-substring beg end))
1140
1141      (set-buffer out-buffer)
1142      (erase-buffer)
1143      (insert string)
1144      (goto-char (point-min)))))
1145
1146
1147 ;; goto word #n starting at current position in buffer `buf'
1148 ;; For ediff, a word is either a string of a-z,A-Z, incl `-' and `_';
1149 ;; or a string of other non-blanks. A blank is a \n\t\f
1150 ;; If `flag' is non-nil, goto the end of the n-th word.
1151 (defun ediff-goto-word (n buf &optional flag)
1152   ;; remember val ediff-forward-word-function has in ctl buf
1153   (let ((fwd-word-fun ediff-forward-word-function))
1154     (ediff-eval-in-buffer buf
1155       (skip-chars-forward ediff-whitespace)
1156       (while (> n 1)
1157         (funcall fwd-word-fun)
1158         (skip-chars-forward ediff-whitespace)
1159         (setq n (1- n)))
1160       (if (and flag (> n 0))
1161           (funcall fwd-word-fun))
1162       (point))))
1163
1164
1165 (provide 'ediff-diff)
1166
1167
1168 ;; ediff-diff.el ends here