lisp/info.el

   1 ;;; info.el --- info package for Emacs
   2
   3 ;; Copyright (C) 1985, 86, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002
   4 ;;  Free Software Foundation, Inc.
   5
   6 ;; Maintainer: FSF
   7 ;; Keywords: help
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation; either version 2, or (at your option)
  14 ;; any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  24 ;; Boston, MA 02111-1307, USA.
  25
  26 ;;; Commentary:
  27
  28 ;; Note that nowadays we expect info files to be made using makeinfo.
  29
  30 ;;; Code:
  31
  32 (eval-when-compile (require 'jka-compr))
  33
  34 (defgroup info nil
  35   "Info subsystem"
  36   :group 'help
  37   :group 'docs)
  38
  39
  40 (defvar Info-history nil
  41   "List of info nodes user has visited.
  42 Each element of list is a list (FILENAME NODENAME BUFFERPOS).")
  43
  44 (defcustom Info-enable-edit nil
  45   "*Non-nil means the \\<Info-mode-map>\\[Info-edit] command in Info can edit the current node.
  46 This is convenient if you want to write info files by hand.
  47 However, we recommend that you not do this.
  48 It is better to write a Texinfo file and generate the Info file from that,
  49 because that gives you a printed manual as well."
  50   :type 'boolean
  51   :group 'info)
  52
  53 (defvar Info-enable-active-nodes nil
  54   "Non-nil allows Info to execute Lisp code associated with nodes.
  55 The Lisp code is executed when the node is selected.")
  56 (put 'Info-enable-active-nodes 'risky-local-variable t)
  57
  58 (defface info-node
  59   '((((class color) (background light)) (:foreground "brown" :weight bold :slant italic))
  60     (((class color) (background dark)) (:foreground "white" :weight bold :slant italic))
  61     (t (:weight bold :slant italic)))
  62   "Face for Info node names."
  63   :group 'info)
  64
  65 (defface info-menu-5
  66   '((((class color)) (:foreground "red1"))
  67     (t (:underline t)))
  68   "Face for the fifth and nineth `*' in an Info menu."
  69   :group 'info)
  70
  71 (defface info-xref
  72   '((((class color) (background light)) (:foreground "magenta4" :weight bold))
  73     (((class color) (background dark)) (:foreground "cyan" :weight bold))
  74     (t (:weight bold)))
  75   "Face for Info cross-references."
  76   :group 'info)
  77
  78 (defcustom Info-fontify-maximum-menu-size 100000
  79   "*Maximum size of menu to fontify if `Info-fontify' is non-nil."
  80   :type 'integer
  81   :group 'info)
  82
  83 (defcustom Info-use-header-line t
  84   "*Non-nil means to put the beginning-of-node links in an emacs header-line.
  85 A header-line does not scroll with the rest of the buffer."
  86   :type 'boolean
  87   :group 'info)
  88
  89 (defface info-header-xref
  90   '((t (:inherit info-xref)))
  91   "Face for Info cross-references in a node header."
  92   :group 'info)
  93
  94 (defface info-header-node
  95   '((t (:inherit info-node)))
  96   "Face for Info nodes in a node header."
  97   :group 'info)
  98
  99 (defvar Info-directory-list nil
 100   "List of directories to search for Info documentation files.
 101 nil means not yet initialized.  In this case, Info uses the environment
 102 variable INFOPATH to initialize it, or `Info-default-directory-list'
 103 if there is no INFOPATH variable in the environment.
 104
 105 When `Info-directory-list' is initialized from the value of
 106 `Info-default-directory-list', and Emacs is installed in one of the
 107 standard directories, the directory of Info files that come with Emacs
 108 is put last (so that local Info files override standard ones).
 109
 110 When `Info-directory-list' is initialized from the value of
 111 `Info-default-directory-list', and Emacs is not installed in one
 112 of the standard directories, the first element of the resulting
 113 list is the directory where Emacs installs the Info files that
 114 come with it.  This is so that Emacs's own manual, which suits the
 115 version of Emacs you are using, will always be found first.  This
 116 is useful when you install an experimental version of Emacs without
 117 removing the standard installation.
 118
 119 If you want to override the order of directories in
 120 `Info-default-directory-list', set INFOPATH in the environment.
 121
 122 If you run the Emacs executable from the `src' directory in the Emacs
 123 source tree, and INFOPATH is not defined, the `info' directory in the
 124 source tree is used as the first element of `Info-directory-list', in
 125 place of the installation Info directory.  This is useful when you run
 126 a version of Emacs without installing it.")
 127
 128 (defcustom Info-additional-directory-list nil
 129   "List of additional directories to search for Info documentation files.
 130 These directories are searched after those in `Info-directory-list', and
 131 they are not searched for merging the `dir' file."
 132   :type '(repeat directory)
 133   :group 'info)
 134
 135 (defcustom Info-scroll-prefer-subnodes t
 136   "*If non-nil, \\<Info-mode-map>\\[Info-scroll-up] in a menu visits subnodes.
 137 If this is non-nil, and you scroll far enough in a node that its menu
 138 appears on the screen, the next \\<Info-mode-map>\\[Info-scroll-up]
 139 moves to a subnode indicated by the following menu item.  This means
 140 that you visit a subnode before getting to the end of the menu.
 141
 142 Setting this option to nil results in behavior similar to the stand-alone
 143 Info reader program, which visits the first subnode from the menu only
 144 when you hit the end of the current node."
 145   :type 'boolean
 146   :group 'info)
 147
 148 (defcustom Info-mode-hook '(turn-on-font-lock)
 149   "Hooks run when `info-mode' is called."
 150   :type 'hook
 151   :group 'info)
 152
 153 (defvar Info-current-file nil
 154   "Info file that Info is now looking at, or nil.
 155 This is the name that was specified in Info, not the actual file name.
 156 It doesn't contain directory names or file name extensions added by Info.
 157 Can also be t when using `Info-on-current-buffer'.")
 158
 159 (defvar Info-current-subfile nil
 160   "Info subfile that is actually in the *info* buffer now.
 161 nil if current info file is not split into subfiles.")
 162
 163 (defvar Info-current-node nil
 164   "Name of node that Info is now looking at, or nil.")
 165
 166 (defvar Info-tag-table-marker nil
 167   "Marker pointing at beginning of current Info file's tag table.
 168 Marker points nowhere if file has no tag table.")
 169
 170 (defvar Info-tag-table-buffer nil
 171   "Buffer used for indirect tag tables.")
 172
 173 (defvar Info-current-file-completions nil
 174   "Cached completion list for current Info file.")
 175
 176 (defvar Info-index-alternatives nil
 177   "List of possible matches for last `Info-index' command.")
 178
 179 (defvar Info-standalone nil
 180   "Non-nil if Emacs was started solely as an Info browser.")
 181 \f
 182 (defvar Info-suffix-list
 183   ;; The MS-DOS list should work both when long file names are
 184   ;; supported (Windows 9X), and when only 8+3 file names are available.
 185   (if (eq system-type 'ms-dos)
 186       '( (".gz"      . "gunzip")
 187          (".z"       . "gunzip")
 188          (".bz2"     . ("bzip2" "-dc"))
 189          (".inz"     . "gunzip")
 190          (".igz"     . "gunzip")
 191          (".info.Z"  . "gunzip")
 192          (".info.gz" . "gunzip")
 193          ("-info.Z"  . "gunzip")
 194          ("-info.gz" . "gunzip")
 195          ("/index.gz". "gunzip")
 196          ("/index.z" . "gunzip")
 197          (".inf"     . nil)
 198          (".info"    . nil)
 199          ("-info"    . nil)
 200          ("/index"   . nil)
 201          (""         . nil))
 202     '( (".info.Z".    "uncompress")
 203        (".info.Y".    "unyabba")
 204        (".info.gz".   "gunzip")
 205        (".info.z".    "gunzip")
 206        (".info.bz2" . ("bzip2" "-dc"))
 207        (".info".      nil)
 208        ("-info.Z".   "uncompress")
 209        ("-info.Y".   "unyabba")
 210        ("-info.gz".  "gunzip")
 211        ("-info.bz2" . ("bzip2" "-dc"))
 212        ("-info.z".   "gunzip")
 213        ("-info".     nil)
 214        ("/index.Z".   "uncompress")
 215        ("/index.Y".   "unyabba")
 216        ("/index.gz".  "gunzip")
 217        ("/index.z".   "gunzip")
 218        ("/index.bz2". ("bzip2" "-dc"))
 219        ("/index".     nil)
 220        (".Z".         "uncompress")
 221        (".Y".         "unyabba")
 222        (".gz".        "gunzip")
 223        (".z".         "gunzip")
 224        (".bz2" .      ("bzip2" "-dc"))
 225        ("".           nil)))
 226   "List of file name suffixes and associated decoding commands.
 227 Each entry should be (SUFFIX . STRING); the file is given to
 228 the command as standard input.
 229
 230 STRING may be a list of strings.  In that case, the first element is
 231 the command name, and the rest are arguments to that command.
 232
 233 If STRING is nil, no decoding is done.
 234 Because the SUFFIXes are tried in order, the empty string should
 235 be last in the list.")
 236
 237 ;; Concatenate SUFFIX onto FILENAME.  SUFFIX should start with a dot.
 238 ;; First, on MS-DOS with no long file names support, delete some of
 239 ;; the extension in FILENAME to make room.
 240 (defun info-insert-file-contents-1 (filename suffix lfn)
 241   (if lfn       ; long file names are supported
 242       (concat filename suffix)
 243     (let* ((sans-exts (file-name-sans-extension filename))
 244            ;; How long is the extension in FILENAME (not counting the dot).
 245            (ext-len (max 0 (- (length filename) (length sans-exts) 1)))
 246            ext-left)
 247       ;; SUFFIX starts with a dot.  If FILENAME already has one,
 248       ;; get rid of the one in SUFFIX (unless suffix is empty).
 249       (or (and (<= ext-len 0)
 250                (not (eq (aref filename (1- (length filename))) ?.)))
 251           (= (length suffix) 0)
 252           (setq suffix (substring suffix 1)))
 253       ;; How many chars of that extension should we keep?
 254       (setq ext-left (min ext-len (max 0 (- 3 (length suffix)))))
 255       ;; Get rid of the rest of the extension, and add SUFFIX.
 256       (concat (substring filename 0 (- (length filename)
 257                                        (- ext-len ext-left)))
 258               suffix))))
 259
 260 (defun info-file-exists-p (filename)
 261   (and (file-exists-p filename)
 262        (not (file-directory-p filename))))
 263
 264 (defun info-insert-file-contents (filename &optional visit)
 265   "Insert the contents of an info file in the current buffer.
 266 Do the right thing if the file has been compressed or zipped."
 267   (let* ((tail Info-suffix-list)
 268          (lfn (or (not (fboundp 'msdos-long-file-names))
 269                   (msdos-long-file-names)))
 270          (check-short (and (fboundp 'msdos-long-file-names)
 271                            lfn))
 272          fullname decoder done)
 273     (if (info-file-exists-p filename)
 274         ;; FILENAME exists--see if that name contains a suffix.
 275         ;; If so, set DECODE accordingly.
 276         (progn
 277           (while (and tail
 278                       (not (string-match
 279                             (concat (regexp-quote (car (car tail))) "$")
 280                             filename)))
 281             (setq tail (cdr tail)))
 282           (setq fullname filename
 283                 decoder (cdr (car tail))))
 284       ;; Try adding suffixes to FILENAME and see if we can find something.
 285       (while (and tail (not done))
 286         (setq fullname (info-insert-file-contents-1 filename
 287                                                     (car (car tail)) lfn))
 288         (if (info-file-exists-p fullname)
 289             (setq done t
 290                   ;; If we found a file with a suffix, set DECODER
 291                   ;; according to the suffix.
 292                   decoder (cdr (car tail)))
 293           ;; When the MS-DOS port runs on Windows, we need to check
 294           ;; the short variant of a long file name as well.
 295           (when check-short
 296             (setq fullname (info-insert-file-contents-1 filename
 297                                                         (car (car tail)) nil))
 298             (if (info-file-exists-p fullname)
 299                 (setq done t
 300                       decoder (cdr (car tail))))))
 301         (setq tail (cdr tail)))
 302       (or tail
 303           (error "Can't find %s or any compressed version of it" filename)))
 304     ;; check for conflict with jka-compr
 305     (if (and (featurep 'jka-compr)
 306              (jka-compr-installed-p)
 307              (jka-compr-get-compression-info fullname))
 308         (setq decoder nil))
 309     (if decoder
 310         (progn
 311           (insert-file-contents-literally fullname visit)
 312           (let ((buffer-read-only nil)
 313                 (coding-system-for-write 'no-conversion)
 314                 (default-directory (or (file-name-directory fullname)
 315                                        default-directory)))
 316             (or (consp decoder)
 317                 (setq decoder (list decoder)))
 318             (apply 'call-process-region (point-min) (point-max)
 319                    (car decoder) t t nil (cdr decoder))))
 320       (insert-file-contents fullname visit))))
 321 \f
 322 (defun info-initialize ()
 323   "Initialize `Info-directory-list', if that hasn't been done yet."
 324   (unless Info-directory-list
 325     (let ((path (getenv "INFOPATH"))
 326           (source (expand-file-name "info/" source-directory))
 327           (sibling (if installation-directory
 328                        (expand-file-name "info/" installation-directory)
 329                      (if invocation-directory
 330                          (let ((infodir (expand-file-name
 331                                          "../info/"
 332                                          invocation-directory)))
 333                            (if (file-exists-p infodir)
 334                                infodir
 335                              (setq infodir (expand-file-name
 336                                             "../../../info/"
 337                                             invocation-directory))
 338                              (and (file-exists-p infodir)
 339                                   infodir))))))
 340           alternative)
 341       (setq Info-directory-list
 342             (prune-directory-list
 343              (if path
 344                  (split-string path (regexp-quote path-separator))
 345                (if (and sibling (file-exists-p sibling))
 346                    ;; Uninstalled, Emacs builddir != srcdir.
 347                    (setq alternative sibling)
 348                  ;; Uninstalled, builddir == srcdir
 349                  (setq alternative source))
 350                (if (or (member alternative Info-default-directory-list)
 351                        ;; On DOS/NT, we use movable executables always,
 352                        ;; and we must always find the Info dir at run time.
 353                        (if (memq system-type '(ms-dos windows-nt))
 354                            nil
 355                          ;; Use invocation-directory for Info
 356                          ;; only if we used it for exec-directory also.
 357                          (not (string= exec-directory
 358                                        (expand-file-name "lib-src/"
 359                                                          installation-directory))))
 360                        (not (file-exists-p alternative)))
 361                    Info-default-directory-list
 362                  ;; `alternative' contains the Info files that came with this
 363                  ;; version, so we should look there first.  `Info-insert-dir'
 364                  ;; currently expects to find `alternative' first on the list.
 365                  (cons alternative
 366                        (reverse (cdr (reverse Info-default-directory-list)))))))))))
 367
 368 ;;;###autoload
 369 (defun info-other-window (&optional file)
 370   "Like `info' but show the Info buffer in another window."
 371   (interactive (if current-prefix-arg
 372                    (list (read-file-name "Info file name: " nil nil t))))
 373   (let (same-window-buffer-names)
 374     (info file)))
 375
 376 ;;;###autoload (add-hook 'same-window-buffer-names "*info*")
 377
 378 ;;;###autoload
 379 (defun info (&optional file)
 380   "Enter Info, the documentation browser.
 381 Optional argument FILE specifies the file to examine;
 382 the default is the top-level directory of Info.
 383 Called from a program, FILE may specify an Info node of the form
 384 `(FILENAME)NODENAME'.
 385
 386 In interactive use, a prefix argument directs this command
 387 to read a file name from the minibuffer.
 388
 389 The search path for Info files is in the variable `Info-directory-list'.
 390 The top-level Info directory is made by combining all the files named `dir'
 391 in all the directories in that path."
 392   (interactive (if current-prefix-arg
 393                    (list (read-file-name "Info file name: " nil nil t))))
 394   (if file
 395       (progn
 396         (pop-to-buffer "*info*")
 397         ;; If argument already contains parentheses, don't add another set
 398         ;; since the argument will then be parsed improperly.  This also
 399         ;; has the added benefit of allowing node names to be included
 400         ;; following the parenthesized filename.
 401         (if (and (stringp file) (string-match "(.*)" file))
 402             (Info-goto-node file)
 403           (Info-goto-node (concat "(" file ")"))))
 404     (if (get-buffer "*info*")
 405         (pop-to-buffer "*info*")
 406       (Info-directory))))
 407
 408 ;;;###autoload
 409 (defun info-standalone ()
 410   "Run Emacs as a standalone Info reader.
 411 Usage:  emacs -f info-standalone [filename]
 412 In standalone mode, \\<Info-mode-map>\\[Info-exit] exits Emacs itself."
 413   (setq Info-standalone t)
 414   (if (and command-line-args-left
 415            (not (string-match "^-" (car command-line-args-left))))
 416       (condition-case err
 417           (progn
 418             (info (car command-line-args-left))
 419             (setq command-line-args-left (cdr command-line-args-left)))
 420         (error (send-string-to-terminal
 421                 (format "%s\n" (if (eq (car-safe err) 'error)
 422                                    (nth 1 err) err)))
 423                (save-buffers-kill-emacs)))
 424     (info)))
 425 \f
 426 ;; See if the accessible portion of the buffer begins with a node
 427 ;; delimiter, and the node header line which follows matches REGEXP.
 428 ;; Typically, this test will be followed by a loop that examines the
 429 ;; rest of the buffer with (search-forward "\n\^_"), and it's a pity
 430 ;; to have the overhead of this special test inside the loop.
 431
 432 ;; This function changes match-data, but supposedly the caller might
 433 ;; want to use the results of re-search-backward.
 434
 435 ;; The return value is the value of point at the beginning of matching
 436 ;; REGEXP, if the function succeeds, nil otherwise.
 437 (defun Info-node-at-bob-matching (regexp)
 438   (and (bobp)                           ; are we at beginning of buffer?
 439        (looking-at "\^_")               ; does it begin with node delimiter?
 440        (let (beg)
 441          (forward-line 1)
 442          (setq beg (point))
 443          (forward-line 1)               ; does the line after delimiter match REGEXP?
 444          (re-search-backward regexp beg t))))
 445
 446 (defun Info-find-node (filename nodename &optional no-going-back)
 447   "Go to an info node specified as separate FILENAME and NODENAME.
 448 NO-GOING-BACK is non-nil if recovering from an error in this function;
 449 it says do not attempt further (recursive) error recovery."
 450   (info-initialize)
 451   ;; Convert filename to lower case if not found as specified.
 452   ;; Expand it.
 453   (if (stringp filename)
 454       (let (temp temp-downcase found)
 455         (setq filename (substitute-in-file-name filename))
 456         (if (string= (downcase filename) "dir")
 457             (setq found t)
 458           (let ((dirs (if (string-match "^\\./" filename)
 459                           ;; If specified name starts with `./'
 460                           ;; then just try current directory.
 461                           '("./")
 462                         (if (file-name-absolute-p filename)
 463                             ;; No point in searching for an
 464                             ;; absolute file name
 465                             '(nil)
 466                           (if Info-additional-directory-list
 467                               (append Info-directory-list
 468                                       Info-additional-directory-list)
 469                             Info-directory-list)))))
 470             ;; Search the directory list for file FILENAME.
 471             (while (and dirs (not found))
 472               (setq temp (expand-file-name filename (car dirs)))
 473               (setq temp-downcase
 474                     (expand-file-name (downcase filename) (car dirs)))
 475               ;; Try several variants of specified name.
 476               (let ((suffix-list Info-suffix-list)
 477                     (lfn (or (not (fboundp 'msdos-long-file-names))
 478                              (msdos-long-file-names))))
 479                 (while (and suffix-list (not found))
 480                   (cond ((info-file-exists-p
 481                           (info-insert-file-contents-1
 482                            temp (car (car suffix-list)) lfn))
 483                          (setq found temp))
 484                         ((info-file-exists-p
 485                           (info-insert-file-contents-1
 486                            temp-downcase (car (car suffix-list)) lfn))
 487                          (setq found temp-downcase))
 488                         ((and (fboundp 'msdos-long-file-names)
 489                               lfn
 490                               (info-file-exists-p
 491                                (info-insert-file-contents-1
 492                                 temp (car (car suffix-list)) nil)))
 493                          (setq found temp)))
 494                   (setq suffix-list (cdr suffix-list))))
 495               (setq dirs (cdr dirs)))))
 496         (if found
 497             (setq filename found)
 498           (error "Info file %s does not exist" filename))))
 499   ;; Record the node we are leaving.
 500   (if (and Info-current-file (not no-going-back))
 501       (setq Info-history
 502             (cons (list Info-current-file Info-current-node (point))
 503                   Info-history)))
 504   ;; Go into info buffer.
 505   (or (eq major-mode 'Info-mode) (pop-to-buffer "*info*"))
 506   (Info-find-node-2 filename nodename no-going-back))
 507
 508 (defun Info-on-current-buffer (&optional nodename)
 509   "Use the `Info-mode' to browse the current info buffer.
 510 If a prefix arg is provided, it queries for the NODENAME which
 511 else defaults to \"Top\"."
 512   (interactive
 513    (list (if current-prefix-arg
 514              (completing-read "Node name: " (Info-build-node-completions)
 515                               nil t "Top"))))
 516   (unless nodename (setq nodename "Top"))
 517   (info-initialize)
 518   (Info-mode)
 519   (set (make-local-variable 'Info-current-file) t)
 520   (Info-find-node-2 nil nodename))
 521
 522 (defun Info-find-in-tag-table-1 (marker regexp case-fold)
 523   "Find a node in a tag table.
 524 MARKER specifies the buffer and position to start searching at.
 525 REGEXP is a regular expression matching nodes or references.  Its first
 526 group should match `Node:' or `Ref:'.
 527 CASE-FOLD t means search for a case-insensitive match.
 528 If a match was found, value is a list (FOUND-ANCHOR POS MODE), where
 529 FOUND-ANCHOR is non-nil if a `Ref:' was matched, POS is the position
 530 where the match was found, and MODE is `major-mode' of the buffer in
 531 which the match was found."
 532   (let ((case-fold-search case-fold)
 533         found-mode guesspos found-anchor)
 534     (save-excursion
 535       (set-buffer (marker-buffer marker))
 536       (goto-char marker)
 537
 538       ;; Search tag table
 539       (beginning-of-line)
 540       (when (re-search-forward regexp nil t)
 541         (list (string-equal "Ref:" (match-string 1))
 542               (+ (point-min) (read (current-buffer)))
 543               major-mode)))))
 544
 545 (defun Info-find-in-tag-table (marker regexp)
 546   "Find a node in a tag table.
 547 MARKER specifies the buffer and position to start searching at.
 548 REGEXP is a regular expression matching nodes or references.  Its first
 549 group should match `Node:' or `Ref:'.
 550 If a match was found, value is a list (FOUND-ANCHOR POS MODE), where
 551 FOUND-ANCHOR is non-nil if a `Ref:' was matched, POS is the position
 552 where the match was found, and MODE is `major-mode' of the buffer in
 553 which the match was found.
 554 This function tries to find a case-sensitive match first, then a
 555 case-insensitive match is tried."
 556   (let ((result (Info-find-in-tag-table-1 marker regexp nil)))
 557     (when (null (car result))
 558       (setq result (Info-find-in-tag-table-1 marker regexp t)))
 559     result))
 560
 561 (defun Info-find-node-in-buffer-1 (regexp case-fold)
 562   "Find a node or anchor in the current buffer.
 563 REGEXP is a regular expression matching nodes or references.  Its first
 564 group should match `Node:' or `Ref:'.
 565 CASE-FOLD t means search for a case-insensitive match.
 566 Value is the position at which a match was found, or nil if not found."
 567   (let ((case-fold-search case-fold)
 568         found)
 569     (save-excursion
 570       (when (Info-node-at-bob-matching regexp)
 571         (setq found (point)))
 572       (while (and (not found)
 573                   (search-forward "\n\^_" nil t))
 574         (forward-line 1)
 575         (let ((beg (point)))
 576           (forward-line 1)
 577           (when (re-search-backward regexp beg t)
 578             (beginning-of-line)
 579             (setq found (point)))))
 580       found)))
 581
 582 (defun Info-find-node-in-buffer (regexp)
 583   "Find a node or anchor in the current buffer.
 584 REGEXP is a regular expression matching nodes or references.  Its first
 585 group should match `Node:' or `Ref:'.
 586 Value is the position at which a match was found, or nil if not found.
 587 This function looks for a case-sensitive match first.  If none is found,
 588 a case-insensitive match is tried."
 589   (or (Info-find-node-in-buffer-1 regexp nil)
 590       (Info-find-node-in-buffer-1 regexp t)))
 591
 592 (defun Info-find-node-2 (filename nodename &optional no-going-back)
 593   (buffer-disable-undo (current-buffer))
 594   (or (eq major-mode 'Info-mode)
 595       (Info-mode))
 596   (widen)
 597   (setq Info-current-node nil)
 598   (unwind-protect
 599       (let ((case-fold-search t)
 600             anchorpos)
 601         ;; Switch files if necessary
 602         (or (null filename)
 603             (equal Info-current-file filename)
 604             (let ((buffer-read-only nil))
 605               (setq Info-current-file nil
 606                     Info-current-subfile nil
 607                     Info-current-file-completions nil
 608                     buffer-file-name nil)
 609               (erase-buffer)
 610               (if (eq filename t)
 611                   (Info-insert-dir)
 612                 (info-insert-file-contents filename nil)
 613                 (setq default-directory (file-name-directory filename)))
 614               (set-buffer-modified-p nil)
 615               ;; See whether file has a tag table.  Record the location if yes.
 616               (goto-char (point-max))
 617               (forward-line -8)
 618               ;; Use string-equal, not equal, to ignore text props.
 619               (if (not (or (string-equal nodename "*")
 620                            (not
 621                             (search-forward "\^_\nEnd tag table\n" nil t))))
 622                   (let (pos)
 623                     ;; We have a tag table.  Find its beginning.
 624                     ;; Is this an indirect file?
 625                     (search-backward "\nTag table:\n")
 626                     (setq pos (point))
 627                     (if (save-excursion
 628                           (forward-line 2)
 629                           (looking-at "(Indirect)\n"))
 630                         ;; It is indirect.  Copy it to another buffer
 631                         ;; and record that the tag table is in that buffer.
 632                         (let ((buf (current-buffer))
 633                               (tagbuf
 634                                (or Info-tag-table-buffer
 635                                    (generate-new-buffer " *info tag table*"))))
 636                           (setq Info-tag-table-buffer tagbuf)
 637                           (save-excursion
 638                             (set-buffer tagbuf)
 639                             (buffer-disable-undo (current-buffer))
 640                             (setq case-fold-search t)
 641                             (erase-buffer)
 642                             (insert-buffer-substring buf))
 643                           (set-marker Info-tag-table-marker
 644                                       (match-end 0) tagbuf))
 645                       (set-marker Info-tag-table-marker pos)))
 646                 (set-marker Info-tag-table-marker nil))
 647               (setq Info-current-file
 648                     (if (eq filename t) "dir" filename))))
 649         ;; Use string-equal, not equal, to ignore text props.
 650         (if (string-equal nodename "*")
 651             (progn (setq Info-current-node nodename)
 652                    (Info-set-mode-line))
 653           ;; Possibilities:
 654           ;;
 655           ;; 1. Anchor found in tag table
 656           ;; 2. Anchor *not* in tag table
 657           ;;
 658           ;; 3. Node found in tag table
 659           ;; 4. Node *not* found in tag table, but found in file
 660           ;; 5. Node *not* in tag table, and *not* in file
 661           ;;
 662           ;; *Or* the same, but in an indirect subfile.
 663
 664           ;; Search file for a suitable node.
 665           (let ((guesspos (point-min))
 666                 (regexp (concat "\\(Node:\\|Ref:\\) *\\("
 667                                 (if (stringp nodename)
 668                                     (regexp-quote nodename)
 669                                   "")
 670                                 "\\) *[,\t\n\177]"))
 671                 (nodepos nil))
 672
 673             (catch 'foo
 674
 675               ;; First, search a tag table, if any
 676               (when (marker-position Info-tag-table-marker)
 677                 (let* ((m Info-tag-table-marker)
 678                        (found (Info-find-in-tag-table m regexp)))
 679
 680                   (when found
 681                     ;; FOUND is (ANCHOR POS MODE).
 682                     (setq guesspos (nth 1 found))
 683
 684                     ;; If this is an indirect file, determine which
 685                     ;; file really holds this node and read it in.
 686                     (unless (eq (nth 2 found) 'Info-mode)
 687                       ;; Note that the current buffer must be the
 688                       ;; *info* buffer on entry to
 689                       ;; Info-read-subfile.  Thus the hackery above.
 690                       (setq guesspos (Info-read-subfile guesspos)))
 691
 692                     ;; Handle anchor
 693                     (when (nth 0 found)
 694                       (goto-char (setq anchorpos guesspos))
 695                       (throw 'foo t)))))
 696
 697               ;; Else we may have a node, which we search for:
 698               (goto-char (max (point-min)
 699                               (- (byte-to-position guesspos) 1000)))
 700
 701               ;; Now search from our advised position (or from beg of
 702               ;; buffer) to find the actual node.  First, check
 703               ;; whether the node is right where we are, in case the
 704               ;; buffer begins with a node.
 705               (let ((pos (Info-find-node-in-buffer regexp)))
 706                 (when pos
 707                   (goto-char pos)
 708                   (throw 'foo t))
 709                 (error "No such anchor in tag table or node in tag table or file: %s"
 710                        nodename)))
 711
 712             (Info-select-node)
 713             (goto-char (or anchorpos (point-min))))))
 714     ;; If we did not finish finding the specified node,
 715     ;; go back to the previous one.
 716     (or Info-current-node no-going-back (null Info-history)
 717         (let ((hist (car Info-history)))
 718           (setq Info-history (cdr Info-history))
 719           (Info-find-node (nth 0 hist) (nth 1 hist) t)
 720           (goto-char (nth 2 hist))))))
 721
 722 ;; Cache the contents of the (virtual) dir file, once we have merged
 723 ;; it for the first time, so we can save time subsequently.
 724 (defvar Info-dir-contents nil)
 725
 726 ;; Cache for the directory we decided to use for the default-directory
 727 ;; of the merged dir text.
 728 (defvar Info-dir-contents-directory nil)
 729
 730 ;; Record the file attributes of all the files from which we
 731 ;; constructed Info-dir-contents.
 732 (defvar Info-dir-file-attributes nil)
 733
 734 (defvar Info-dir-file-name nil)
 735
 736 ;; Construct the Info directory node by merging the files named `dir'
 737 ;; from various directories.  Set the *info* buffer's
 738 ;; default-directory to the first directory we actually get any text
 739 ;; from.
 740 (defun Info-insert-dir ()
 741   (if (and Info-dir-contents Info-dir-file-attributes
 742            ;; Verify that none of the files we used has changed
 743            ;; since we used it.
 744            (eval (cons 'and
 745                        (mapcar (lambda (elt)
 746                                  (let ((curr (file-attributes
 747                                               ;; Handle symlinks
 748                                               (file-truename (car elt)))))
 749
 750                                    ;; Don't compare the access time.
 751                                    (if curr (setcar (nthcdr 4 curr) 0))
 752                                    (setcar (nthcdr 4 (cdr elt)) 0)
 753                                    (equal (cdr elt) curr)))
 754                                Info-dir-file-attributes))))
 755       (progn
 756         (insert Info-dir-contents)
 757         (goto-char (point-min)))
 758     (let ((dirs (if Info-additional-directory-list
 759                               (append Info-directory-list
 760                                       Info-additional-directory-list)
 761                             Info-directory-list))
 762           ;; Bind this in case the user sets it to nil.
 763           (case-fold-search t)
 764           ;; This is set non-nil if we find a problem in some input files.
 765           problems
 766           buffers buffer others nodes dirs-done)
 767
 768       (setq Info-dir-file-attributes nil)
 769
 770       ;; Search the directory list for the directory file.
 771       (while dirs
 772         (let ((truename (file-truename (expand-file-name (car dirs)))))
 773           (or (member truename dirs-done)
 774               (member (directory-file-name truename) dirs-done)
 775               ;; Try several variants of specified name.
 776               ;; Try upcasing, appending `.info', or both.
 777               (let* (file
 778                      (attrs
 779                       (or
 780                        (progn (setq file (expand-file-name "dir" truename))
 781                               (file-attributes file))
 782                        (progn (setq file (expand-file-name "DIR" truename))
 783                               (file-attributes file))
 784                        (progn (setq file (expand-file-name "dir.info" truename))
 785                               (file-attributes file))
 786                        (progn (setq file (expand-file-name "DIR.INFO" truename))
 787                               (file-attributes file)))))
 788                 (setq dirs-done
 789                       (cons truename
 790                             (cons (directory-file-name truename)
 791                                   dirs-done)))
 792                 (if attrs
 793                     (save-excursion
 794                       (or buffers
 795                           (message "Composing main Info directory..."))
 796                       (set-buffer (generate-new-buffer " info dir"))
 797                       (condition-case nil
 798                           (progn
 799                             (insert-file-contents file)
 800                             (make-local-variable 'Info-dir-file-name)
 801                             (setq Info-dir-file-name file)
 802                             (setq buffers (cons (current-buffer) buffers)
 803                                   Info-dir-file-attributes
 804                                   (cons (cons file attrs)
 805                                         Info-dir-file-attributes)))
 806                         (error (kill-buffer (current-buffer))))))))
 807           (or (cdr dirs) (setq Info-dir-contents-directory
 808                                (file-name-as-directory (car dirs))))
 809           (setq dirs (cdr dirs))))
 810
 811       (or buffers
 812           (error "Can't find the Info directory node"))
 813       ;; Distinguish the dir file that comes with Emacs from all the
 814       ;; others.  Yes, that is really what this is supposed to do.
 815       ;; The definition of `Info-directory-list' puts it first on that
 816       ;; list and so last in `buffers' at this point.
 817       (setq buffer (car (last buffers))
 818             others (delq buffer buffers))
 819
 820       ;; Insert the entire original dir file as a start; note that we've
 821       ;; already saved its default directory to use as the default
 822       ;; directory for the whole concatenation.
 823       (insert-buffer buffer)
 824
 825       ;; Look at each of the other buffers one by one.
 826       (while others
 827         (let ((other (car others))
 828               ;; Bind this in case the user sets it to nil.
 829               (case-fold-search t)
 830               this-buffer-nodes)
 831           ;; In each, find all the menus.
 832           (save-excursion
 833             (set-buffer other)
 834             (goto-char (point-min))
 835             ;; Find each menu, and add an elt to NODES for it.
 836             (while (re-search-forward "^\\* Menu:" nil t)
 837               (let (beg nodename end)
 838                 (forward-line 1)
 839                 (while (and (eolp) (not (eobp)))
 840                   (forward-line 1))
 841                 (setq beg (point))
 842                 (or (search-backward "\n\^_" nil 'move)
 843                     (looking-at "\^_")
 844                     (signal 'search-failed (list "\n\^_")))
 845                 (search-forward "Node: ")
 846                 (setq nodename (Info-following-node-name))
 847                 (search-forward "\n\^_" nil 'move)
 848                 (beginning-of-line)
 849                 (setq end (point))
 850                 (setq this-buffer-nodes
 851                       (cons (list nodename other beg end)
 852                             this-buffer-nodes))))
 853             (if (assoc-ignore-case "top" this-buffer-nodes)
 854                 (setq nodes (nconc this-buffer-nodes nodes))
 855               (setq problems t)
 856               (message "No `top' node in %s" Info-dir-file-name))))
 857         (setq others (cdr others)))
 858       ;; Add to the main menu a menu item for each other node.
 859       (let ((case-fold-search t)
 860             (re-search-forward "^\\* Menu:")))
 861       (forward-line 1)
 862       (let ((menu-items '("top"))
 863             (nodes nodes)
 864             (case-fold-search t)
 865             (end (save-excursion (search-forward "\^_" nil t) (point))))
 866         (while nodes
 867           (let ((nodename (car (car nodes))))
 868             (save-excursion
 869               (or (member (downcase nodename) menu-items)
 870                   (re-search-forward (concat "^\\* +"
 871                                              (regexp-quote nodename)
 872                                              "::")
 873                                      end t)
 874                   (progn
 875                     (insert "* " nodename "::" "\n")
 876                     (setq menu-items (cons nodename menu-items))))))
 877           (setq nodes (cdr nodes))))
 878       ;; Now take each node of each of the other buffers
 879       ;; and merge it into the main buffer.
 880       (while nodes
 881         (let ((case-fold-search t)
 882               (nodename (car (car nodes))))
 883           (goto-char (point-min))
 884           ;; Find the like-named node in the main buffer.
 885           (if (re-search-forward (concat "^\^_.*\n.*Node: "
 886                                          (regexp-quote nodename)
 887                                          "[,\n\t]")
 888                                  nil t)
 889               (progn
 890                 (search-forward "\n\^_" nil 'move)
 891                 (beginning-of-line)
 892                 (insert "\n"))
 893             ;; If none exists, add one.
 894             (goto-char (point-max))
 895             (insert "\^_\nFile: dir\tNode: " nodename "\n\n* Menu:\n\n"))
 896           ;; Merge the text from the other buffer's menu
 897           ;; into the menu in the like-named node in the main buffer.
 898           (apply 'insert-buffer-substring (cdr (car nodes))))
 899         (setq nodes (cdr nodes)))
 900       ;; Kill all the buffers we just made.
 901       (while buffers
 902         (kill-buffer (car buffers))
 903         (setq buffers (cdr buffers)))
 904       (goto-char (point-min))
 905       (if problems
 906           (message "Composing main Info directory...problems encountered, see `*Messages*'")
 907         (message "Composing main Info directory...done")))
 908     (setq Info-dir-contents (buffer-string)))
 909   (setq default-directory Info-dir-contents-directory))
 910
 911 ;; Note that on entry to this function the current-buffer must be the
 912 ;; *info* buffer; not the info tags buffer.
 913 (defun Info-read-subfile (nodepos)
 914   ;; NODEPOS is either a position (in the Info file as a whole,
 915   ;; not relative to a subfile) or the name of a subfile.
 916   (let (lastfilepos
 917         lastfilename)
 918     (if (numberp nodepos)
 919         (save-excursion
 920           (set-buffer (marker-buffer Info-tag-table-marker))
 921           (goto-char (point-min))
 922           (or (looking-at "\^_")
 923               (search-forward "\n\^_"))
 924           (forward-line 2)
 925           (catch 'foo
 926             (while (not (looking-at "\^_"))
 927               (if (not (eolp))
 928                   (let ((beg (point))
 929                         thisfilepos thisfilename)
 930                     (search-forward ": ")
 931                     (setq thisfilename  (buffer-substring beg (- (point) 2)))
 932                     (setq thisfilepos (+ (point-min) (read (current-buffer))))
 933                     ;; read in version 19 stops at the end of number.
 934                     ;; Advance to the next line.
 935                     (forward-line 1)
 936                     (if (> thisfilepos nodepos)
 937                         (throw 'foo t))
 938                     (setq lastfilename thisfilename)
 939                     (setq lastfilepos thisfilepos))
 940                 (forward-line 1)))))
 941       (setq lastfilename nodepos)
 942       (setq lastfilepos 0))
 943     ;; Assume previous buffer is in Info-mode.
 944     ;; (set-buffer (get-buffer "*info*"))
 945     (or (equal Info-current-subfile lastfilename)
 946         (let ((buffer-read-only nil))
 947           (setq buffer-file-name nil)
 948           (widen)
 949           (erase-buffer)
 950           (info-insert-file-contents lastfilename)
 951           (set-buffer-modified-p nil)
 952           (setq Info-current-subfile lastfilename)))
 953     ;; Widen in case we are in the same subfile as before.
 954     (widen)
 955     (goto-char (point-min))
 956     (if (looking-at "\^_")
 957         (forward-char 1)
 958       (search-forward "\n\^_"))
 959     (if (numberp nodepos)
 960         (+ (- nodepos lastfilepos) (point)))))
 961
 962 (defvar Info-header-line nil
 963   "If the info node header is hidden, the text of the header.")
 964 (put 'Info-header-line 'risky-local-variable t)
 965
 966 (defun Info-select-node ()
 967 "Select the info node that point is in.
 968 Bind this in case the user sets it to nil."
 969   (let ((case-fold-search t))
 970     (save-excursion
 971       ;; Find beginning of node.
 972       (if (search-backward "\n\^_" nil 'move)
 973           (forward-line 2)
 974         (if (looking-at "\^_")
 975             (forward-line 1)
 976           (signal 'search-failed (list "\n\^_"))))
 977       ;; Get nodename spelled as it is in the node.
 978       (re-search-forward "Node:[ \t]*")
 979       (setq Info-current-node
 980             (buffer-substring-no-properties (point)
 981                                             (progn
 982                                               (skip-chars-forward "^,\t\n")
 983                                               (point))))
 984       (Info-set-mode-line)
 985       ;; Find the end of it, and narrow.
 986       (beginning-of-line)
 987       (let (active-expression)
 988         ;; Narrow to the node contents
 989         (narrow-to-region (point)
 990                           (if (re-search-forward "\n[\^_\f]" nil t)
 991                               (prog1
 992                                   (1- (point))
 993                                 (if (looking-at "[\n\^_\f]*execute: ")
 994                                     (progn
 995                                       (goto-char (match-end 0))
 996                                       (setq active-expression
 997                                             (read (current-buffer))))))
 998                             (point-max)))
 999         (if Info-enable-active-nodes (eval active-expression))
1000         (Info-fontify-node)
1001         (if Info-use-header-line
1002             (progn
1003               (setq Info-header-line
1004                     (get-text-property (point-min) 'header-line))
1005               (setq header-line-format 'Info-header-line)
1006 ;;; It is useful to be able to copy the links line out of the buffer
1007 ;;; with M-w.
1008 ;;;           (narrow-to-region (1+ header-end) (point-max))
1009               )
1010           (setq Info-header-line nil)
1011           (setq header-line-format nil)) ; so the header line isn't displayed
1012         (run-hooks 'Info-selection-hook)))))
1013
1014 (defun Info-set-mode-line ()
1015   (setq mode-line-buffer-identification
1016         (nconc (propertized-buffer-identification "%b")
1017                (list
1018                 (concat " ("
1019                         (file-name-nondirectory
1020                          (if (stringp Info-current-file)
1021                              Info-current-file
1022                            (or buffer-file-name "")))
1023                         ") "
1024                         (or Info-current-node ""))))))
1025 \f
1026 ;; Go to an info node specified with a filename-and-nodename string
1027 ;; of the sort that is found in pointers in nodes.
1028
1029 (defun Info-goto-node (nodename &optional fork)
1030   "Go to info node named NODENAME.  Give just NODENAME or (FILENAME)NODENAME.
1031 If NODENAME is of the form (FILENAME)NODENAME, the node is in the Info file
1032 FILENAME; otherwise, NODENAME should be in the current Info file (or one of
1033 its sub-files).
1034 Completion is available, but only for node names in the current Info file.
1035 If FORK is non-nil (interactively with a prefix arg), show the node in
1036 a new info buffer.
1037 If FORK is a string, it is the name to use for the new buffer."
1038   (interactive (list (Info-read-node-name "Go to node: ") current-prefix-arg))
1039   (info-initialize)
1040   (if fork
1041       (set-buffer
1042        (clone-buffer (concat "*info-" (if (stringp fork) fork nodename) "*") t)))
1043   (let (filename)
1044     (string-match "\\s *\\((\\s *\\([^\t)]*\\)\\s *)\\s *\\|\\)\\(.*\\)"
1045                   nodename)
1046     (setq filename (if (= (match-beginning 1) (match-end 1))
1047                        ""
1048                      (substring nodename (match-beginning 2) (match-end 2)))
1049           nodename (substring nodename (match-beginning 3) (match-end 3)))
1050     (let ((trim (string-match "\\s *\\'" filename)))
1051       (if trim (setq filename (substring filename 0 trim))))
1052     (let ((trim (string-match "\\s *\\'" nodename)))
1053       (if trim (setq nodename (substring nodename 0 trim))))
1054     (if transient-mark-mode (deactivate-mark))
1055     (Info-find-node (if (equal filename "") nil filename)
1056                     (if (equal nodename "") "Top" nodename))))
1057
1058 (defvar Info-read-node-completion-table)
1059
1060 ;; This function is used as the "completion table" while reading a node name.
1061 ;; It does completion using the alist in Info-read-node-completion-table
1062 ;; unless STRING starts with an open-paren.
1063 (defun Info-read-node-name-1 (string predicate code)
1064   (cond
1065    ;; First complete embedded file names.
1066    ((string-match "\\`([^)]*\\'" string)
1067     (let ((file (substring string 1)))
1068       (cond
1069        ((eq code nil)
1070         (let ((comp (try-completion file 'locate-file-completion
1071                                     (cons Info-directory-list
1072                                           (mapcar 'car Info-suffix-list)))))
1073           (cond
1074            ((eq comp t) (concat string ")"))
1075            (comp (concat "(" comp)))))
1076        ((eq code t) (all-completions file 'locate-file-completion
1077                                      (cons Info-directory-list
1078                                            (mapcar 'car Info-suffix-list))))
1079        (t nil))))
1080    ;; If a file name was given, then any node is fair game.
1081    ((string-match "\\`(" string)
1082     (cond
1083      ((eq code nil) string)
1084      ((eq code t) nil)
1085      (t t)))
1086    ;; Otherwise use Info-read-node-completion-table.
1087    ((eq code nil)
1088     (try-completion string Info-read-node-completion-table predicate))
1089    ((eq code t)
1090     (all-completions string Info-read-node-completion-table predicate))
1091    (t
1092     (test-completion string Info-read-node-completion-table predicate))))
1093
1094 (defun Info-read-node-name (prompt &optional default)
1095   (let* ((completion-ignore-case t)
1096          (Info-read-node-completion-table (Info-build-node-completions))
1097          (nodename (completing-read prompt 'Info-read-node-name-1 nil t)))
1098     (if (equal nodename "")
1099         (or default
1100             (Info-read-node-name prompt))
1101       nodename)))
1102
1103 (defun Info-build-node-completions ()
1104   (or Info-current-file-completions
1105       (let ((compl nil)
1106             ;; Bind this in case the user sets it to nil.
1107             (case-fold-search t)
1108             (node-regexp "Node: *\\([^,\n]*\\) *[,\n\t]"))
1109         (save-excursion
1110           (save-restriction
1111             (if (marker-buffer Info-tag-table-marker)
1112                 (let ((marker Info-tag-table-marker))
1113                   (set-buffer (marker-buffer marker))
1114                   (widen)
1115                   (goto-char marker)
1116                   (while (re-search-forward "\n\\(Node\\|Ref\\): \\(.*\\)\177" nil t)
1117                     (setq compl
1118                           (cons (list (match-string-no-properties 2))
1119                                 compl))))
1120               (widen)
1121               (goto-char (point-min))
1122               ;; If the buffer begins with a node header, process that first.
1123               (if (Info-node-at-bob-matching node-regexp)
1124                   (setq compl (list (match-string-no-properties 1))))
1125               ;; Now for the rest of the nodes.
1126               (while (search-forward "\n\^_" nil t)
1127                 (forward-line 1)
1128                 (let ((beg (point)))
1129                   (forward-line 1)
1130                   (if (re-search-backward node-regexp beg t)
1131                       (setq compl
1132                             (cons (list (match-string-no-properties 1))
1133                                   compl))))))))
1134         (setq compl (cons '("*") compl))
1135         (set (make-local-variable 'Info-current-file-completions) compl))))
1136 \f
1137 (defun Info-restore-point (hl)
1138   "If this node has been visited, restore the point value when we left."
1139   (while hl
1140     (if (and (equal (nth 0 (car hl)) Info-current-file)
1141              ;; Use string-equal, not equal, to ignore text props.
1142              (string-equal (nth 1 (car hl)) Info-current-node))
1143         (progn
1144           (goto-char (nth 2 (car hl)))
1145           (setq hl nil))                ;terminate the while at next iter
1146       (setq hl (cdr hl)))))
1147 \f
1148 (defvar Info-search-history nil
1149   "The history list for `Info-search'.")
1150
1151 (defun Info-search (regexp)
1152   "Search for REGEXP, starting from point, and select node it's found in."
1153   (interactive (list (read-string
1154                       (if Info-search-history
1155                           (format "Regexp search (default `%s'): "
1156                                   (car Info-search-history))
1157                         "Regexp search: ")
1158                       nil 'Info-search-history)))
1159   (when transient-mark-mode
1160     (deactivate-mark))
1161   (when (equal regexp "")
1162     (setq regexp (car Info-search-history)))
1163   (when regexp
1164     (let ((found ()) current
1165           (onode Info-current-node)
1166           (ofile Info-current-file)
1167           (opoint (point))
1168           (ostart (window-start))
1169           (osubfile Info-current-subfile))
1170       (save-excursion
1171         (save-restriction
1172           (widen)
1173           (if (null Info-current-subfile)
1174               (progn (re-search-forward regexp) (setq found (point)))
1175             (condition-case err
1176                 (progn (re-search-forward regexp) (setq found (point)))
1177               (search-failed nil)))))
1178       (if (not found)                   ;can only happen in subfile case -- else would have erred
1179           (unwind-protect
1180               (let ((list ()))
1181                 (save-excursion
1182                   (set-buffer (marker-buffer Info-tag-table-marker))
1183                   (goto-char (point-min))
1184                   (search-forward "\n\^_\nIndirect:")
1185                   (save-restriction
1186                     (narrow-to-region (point)
1187                                       (progn (search-forward "\n\^_")
1188                                              (1- (point))))
1189                     (goto-char (point-min))
1190                     (search-forward (concat "\n" osubfile ": "))
1191                     (beginning-of-line)
1192                     (while (not (eobp))
1193                       (re-search-forward "\\(^.*\\): [0-9]+$")
1194                       (goto-char (+ (match-end 1) 2))
1195                       (setq list (cons (cons (read (current-buffer))
1196                                              (match-string-no-properties 1))
1197                                        list))
1198                       (goto-char (1+ (match-end 0))))
1199                     (setq list (nreverse list)
1200                           current (car (car list))
1201                           list (cdr list))))
1202                 (while list
1203                   (message "Searching subfile %s..." (cdr (car list)))
1204                   (Info-read-subfile (car (car list)))
1205                   (setq list (cdr list))
1206                   (if (re-search-forward regexp nil t)
1207                       (setq found (point) list ())))
1208                 (if found
1209                     (message "")
1210                   (signal 'search-failed (list regexp))))
1211             (if (not found)
1212                 (progn (Info-read-subfile osubfile)
1213                        (goto-char opoint)
1214                        (Info-select-node)
1215                        (set-window-start (selected-window) ostart)))))
1216       (widen)
1217       (goto-char found)
1218       (Info-select-node)
1219       ;; Use string-equal, not equal, to ignore text props.
1220       (or (and (string-equal onode Info-current-node)
1221                (equal ofile Info-current-file))
1222           (setq Info-history (cons (list ofile onode opoint)
1223                                    Info-history))))))
1224 \f
1225 (defun Info-extract-pointer (name &optional errorname)
1226   "Extract the value of the node-pointer named NAME.
1227 If there is none, use ERRORNAME in the error message;
1228 if ERRORNAME is nil, just return nil.
1229 Bind this in case the user sets it to nil."
1230   (let ((case-fold-search t))
1231     (save-excursion
1232       (save-restriction
1233         (goto-char (point-min))
1234 ;;;     (when Info-header-line
1235 ;;;       ;; expose the header line in the buffer
1236 ;;;       (widen)
1237 ;;;       (forward-line -1))
1238         (let ((bound (point)))
1239           (forward-line 1)
1240           (cond ((re-search-backward (concat name ":") bound t)
1241                  (goto-char (match-end 0))
1242                  (Info-following-node-name))
1243                 ((not (eq errorname t))
1244                  (error "Node has no %s"
1245                         (capitalize (or errorname name))))))))))
1246
1247 (defun Info-following-node-name (&optional allowedchars)
1248   "Return the node name in the buffer following point.
1249 ALLOWEDCHARS, if non-nil, goes within [...] to make a regexp
1250 saying which chars may appear in the node name."
1251   (skip-chars-forward " \t")
1252   (buffer-substring-no-properties
1253    (point)
1254    (progn
1255      (while (looking-at (concat "[" (or allowedchars "^,\t\n") "]"))
1256        (skip-chars-forward (concat (or allowedchars "^,\t\n") "("))
1257        (if (looking-at "(")
1258            (skip-chars-forward "^)")))
1259      (skip-chars-backward " ")
1260      (point))))
1261
1262 (defun Info-next ()
1263   "Go to the next node of this node."
1264   (interactive)
1265   (Info-goto-node (Info-extract-pointer "next")))
1266
1267 (defun Info-prev ()
1268   "Go to the previous node of this node."
1269   (interactive)
1270   (Info-goto-node (Info-extract-pointer "prev[ious]*" "previous")))
1271
1272 (defun Info-up (&optional same-file)
1273   "Go to the superior node of this node.
1274 If SAME-FILE is non-nil, do not move to a different Info file."
1275   (interactive)
1276   (let ((node (Info-extract-pointer "up")))
1277     (and (or same-file (not (stringp Info-current-file)))
1278          (string-match "^(" node)
1279          (error "Up node is in another Info file"))
1280     (Info-goto-node node))
1281   (Info-restore-point Info-history))
1282
1283 (defun Info-last ()
1284   "Go back to the last node visited."
1285   (interactive)
1286   (or Info-history
1287       (error "This is the first Info node you looked at"))
1288   (let (filename nodename opoint)
1289     (setq filename (car (car Info-history)))
1290     (setq nodename (car (cdr (car Info-history))))
1291     (setq opoint (car (cdr (cdr (car Info-history)))))
1292     (setq Info-history (cdr Info-history))
1293     (Info-find-node filename nodename)
1294     (setq Info-history (cdr Info-history))
1295     (goto-char opoint)))
1296
1297 ;;;###autoload
1298 (defun Info-directory ()
1299   "Go to the Info directory node."
1300   (interactive)
1301   (Info-find-node "dir" "top"))
1302 \f
1303 (defun Info-follow-reference (footnotename)
1304   "Follow cross reference named FOOTNOTENAME to the node it refers to.
1305 FOOTNOTENAME may be an abbreviation of the reference name."
1306   (interactive
1307    (let ((completion-ignore-case t)
1308          (case-fold-search t)
1309          completions default alt-default (start-point (point)) str i bol eol)
1310      (save-excursion
1311        ;; Store end and beginning of line.
1312        (end-of-line)
1313        (setq eol (point))
1314        (beginning-of-line)
1315        (setq bol (point))
1316
1317        (goto-char (point-min))
1318        (while (re-search-forward "\\*note[ \n\t]*\\([^:]*\\):" nil t)
1319          (setq str (buffer-substring-no-properties
1320                     (match-beginning 1)
1321                     (1- (point))))
1322          ;; See if this one should be the default.
1323          (and (null default)
1324               (<= (match-beginning 0) start-point)
1325               (<= start-point (point))
1326               (setq default t))
1327          ;; See if this one should be the alternate default.
1328          (and (null alt-default)
1329               (and (<= bol (match-beginning 0))
1330                    (<= (point) eol))
1331               (setq alt-default t))
1332          (setq i 0)
1333          (while (setq i (string-match "[ \n\t]+" str i))
1334            (setq str (concat (substring str 0 i) " "
1335                              (substring str (match-end 0))))
1336            (setq i (1+ i)))
1337          ;; Record as a completion and perhaps as default.
1338          (if (eq default t) (setq default str))
1339          (if (eq alt-default t) (setq alt-default str))
1340          ;; Don't add this string if it's a duplicate.
1341          ;; We use a loop instead of "(assoc str completions)" because
1342          ;; we want to do a case-insensitive compare.
1343          (let ((tail completions)
1344                (tem (downcase str)))
1345            (while (and tail
1346                        (not (string-equal tem (downcase (car (car tail))))))
1347              (setq tail (cdr tail)))
1348            (or tail
1349                (setq completions
1350                      (cons (cons str nil)
1351                            completions))))))
1352      ;; If no good default was found, try an alternate.
1353      (or default
1354          (setq default alt-default))
1355      ;; If only one cross-reference found, then make it default.
1356      (if (eq (length completions) 1)
1357          (setq default (car (car completions))))
1358      (if completions
1359          (let ((input (completing-read (if default
1360                                            (concat
1361                                             "Follow reference named: (default "
1362                                             default ") ")
1363                                          "Follow reference named: ")
1364                                        completions nil t)))
1365            (list (if (equal input "")
1366                      default input)))
1367        (error "No cross-references in this node"))))
1368
1369   (unless footnotename
1370     (error "No reference was specified"))
1371
1372   (let (target beg i (str (concat "\\*note " (regexp-quote footnotename)))
1373                (case-fold-search t))
1374     (while (setq i (string-match " " str i))
1375       (setq str (concat (substring str 0 i) "[ \t\n]+" (substring str (1+ i))))
1376       (setq i (+ i 6)))
1377     (save-excursion
1378       (goto-char (point-min))
1379       (or (re-search-forward str nil t)
1380           (error "No cross-reference named %s" footnotename))
1381       (goto-char (+ (match-beginning 0) 5))
1382       (setq target
1383             (Info-extract-menu-node-name "Bad format cross reference" t)))
1384     (while (setq i (string-match "[ \t\n]+" target i))
1385       (setq target (concat (substring target 0 i) " "
1386                            (substring target (match-end 0))))
1387       (setq i (+ i 1)))
1388     (Info-goto-node target)))
1389
1390 (defun Info-extract-menu-node-name (&optional errmessage multi-line)
1391   (skip-chars-forward " \t\n")
1392   (let ((beg (point))
1393         str i)
1394     (skip-chars-forward "^:")
1395     (forward-char 1)
1396     (setq str
1397           (if (looking-at ":")
1398               (buffer-substring-no-properties beg (1- (point)))
1399             (skip-chars-forward " \t\n")
1400             (Info-following-node-name (if multi-line "^.,\t" "^.,\t\n"))))
1401     (replace-regexp-in-string "[ \n]+" " " str)))
1402
1403 ;; No one calls this.
1404 ;;(defun Info-menu-item-sequence (list)
1405 ;;  (while list
1406 ;;    (Info-menu (car list))
1407 ;;    (setq list (cdr list))))
1408
1409 (defvar Info-complete-menu-buffer)
1410 (defvar Info-complete-next-re nil)
1411 (defvar Info-complete-cache nil)
1412
1413 (defun Info-complete-menu-item (string predicate action)
1414   ;; This uses two dynamically bound variables:
1415   ;; - `Info-complete-menu-buffer' which contains the buffer in which
1416   ;; is the menu of items we're trying to complete.
1417   ;; - `Info-complete-next-re' which, if non-nil, indicates that we should
1418   ;; also look for menu items in subsequent nodes as long as those
1419   ;; nodes' names match `Info-complete-next-re'.  This feature is currently
1420   ;; only used for completion in Info-index.
1421   (save-excursion
1422     (set-buffer Info-complete-menu-buffer)
1423     (let ((completion-ignore-case t)
1424           (case-fold-search t)
1425           (orignode Info-current-node)
1426           nextnode)
1427       (goto-char (point-min))
1428       (search-forward "\n* Menu:")
1429       (if (not (memq action '(nil t)))
1430           (re-search-forward
1431            (concat "\n\\* +" (regexp-quote string) ":") nil t)
1432         (let ((pattern (concat "\n\\* +\\("
1433                                (regexp-quote string)
1434                                "[^:\t\n]*\\):"))
1435               completions)
1436           ;; Check the cache.
1437           (if (and (equal (nth 0 Info-complete-cache) Info-current-file)
1438                    (equal (nth 1 Info-complete-cache) Info-current-node)
1439                    (equal (nth 2 Info-complete-cache) Info-complete-next-re)
1440                    (let ((prev (nth 3 Info-complete-cache)))
1441                      (eq t (compare-strings string 0 (length prev)
1442                                             prev 0 nil t))))
1443               ;; We can reuse the previous list.
1444               (setq completions (nth 4 Info-complete-cache))
1445             ;; The cache can't be used.
1446             (while
1447                 (progn
1448                   (while (re-search-forward pattern nil t)
1449                     (push (match-string-no-properties 1)
1450                           completions))
1451                   ;; Check subsequent nodes if applicable.
1452                   (and Info-complete-next-re
1453                        (setq nextnode (Info-extract-pointer "next" t))
1454                        (string-match Info-complete-next-re nextnode)))
1455               (Info-goto-node nextnode))
1456             ;; Go back to the start node (for the next completion).
1457             (unless (equal Info-current-node orignode)
1458               (Info-goto-node orignode))
1459             ;; Update the cache.
1460             (setq Info-complete-cache
1461                   (list Info-current-file Info-current-node
1462                         Info-complete-next-re string completions)))
1463           (if action
1464               (all-completions string completions predicate)
1465             (try-completion string completions predicate)))))))
1466
1467
1468 (defun Info-menu (menu-item &optional fork)
1469   "Go to the node pointed to by the menu item named (or abbreviated) MENU-ITEM.
1470 The menu item should one of those listed in the current node's menu.
1471 Completion is allowed, and the default menu item is the one point is on.
1472 If FORK is non-nil (interactively with a prefix arg), show the node in
1473 a new info buffer.  If FORK is a string, it is the name to use for the
1474 new buffer."
1475   (interactive
1476    (let ((completions '())
1477          ;; If point is within a menu item, use that item as the default
1478          (default nil)
1479          (p (point))
1480          beg
1481          (last nil)
1482          (case-fold-search t))
1483      (save-excursion
1484        (goto-char (point-min))
1485        (if (not (search-forward "\n* menu:" nil t))
1486            (error "No menu in this node"))
1487        (setq beg (point))
1488        (and (< (point) p)
1489             (save-excursion
1490               (goto-char p)
1491               (end-of-line)
1492               (if (re-search-backward "\n\\* +\\([^:\t\n]*\\):" beg t)
1493                   (setq default (match-string-no-properties 1))))))
1494      (let ((item nil))
1495        (while (null item)
1496          (setq item (let ((completion-ignore-case t)
1497                           (Info-complete-menu-buffer (current-buffer)))
1498                       (completing-read (if default
1499                                            (format "Menu item (default %s): "
1500                                                    default)
1501                                          "Menu item: ")
1502                                        'Info-complete-menu-item nil t)))
1503          ;; we rely on the fact that completing-read accepts an input
1504          ;; of "" even when the require-match argument is true and ""
1505          ;; is not a valid possibility
1506          (if (string= item "")
1507              (if default
1508                  (setq item default)
1509                ;; ask again
1510                (setq item nil))))
1511        (list item current-prefix-arg))))
1512   ;; there is a problem here in that if several menu items have the same
1513   ;; name you can only go to the node of the first with this command.
1514   (Info-goto-node (Info-extract-menu-item menu-item) (if fork menu-item)))
1515
1516 (defun Info-extract-menu-item (menu-item)
1517   (setq menu-item (regexp-quote menu-item))
1518   (let ((case-fold-search t))
1519     (save-excursion
1520       (let ((case-fold-search t))
1521         (goto-char (point-min))
1522         (or (search-forward "\n* menu:" nil t)
1523             (error "No menu in this node"))
1524         (or (re-search-forward (concat "\n\\* +" menu-item ":") nil t)
1525             (re-search-forward (concat "\n\\* +" menu-item) nil t)
1526             (error "No such item in menu"))
1527         (beginning-of-line)
1528         (forward-char 2)
1529         (Info-extract-menu-node-name)))))
1530
1531 ;; If COUNT is nil, use the last item in the menu.
1532 (defun Info-extract-menu-counting (count)
1533   (let ((case-fold-search t))
1534     (save-excursion
1535       (let ((case-fold-search t))
1536         (goto-char (point-min))
1537         (or (search-forward "\n* menu:" nil t)
1538             (error "No menu in this node"))
1539         (if count
1540             (or (search-forward "\n* " nil t count)
1541                 (error "Too few items in menu"))
1542           (while (search-forward "\n* " nil t)
1543             nil))
1544         (Info-extract-menu-node-name)))))
1545
1546 (defun Info-nth-menu-item ()
1547   "Go to the node of the Nth menu item.
1548 N is the digit argument used to invoke this command."
1549   (interactive)
1550   (Info-goto-node
1551    (Info-extract-menu-counting
1552     (- (aref (this-command-keys) (1- (length (this-command-keys)))) ?0))))
1553
1554 (defun Info-top-node ()
1555   "Go to the Top node of this file."
1556   (interactive)
1557   (Info-goto-node "Top"))
1558
1559 (defun Info-final-node ()
1560   "Go to the final node in this file."
1561   (interactive)
1562   (Info-goto-node "Top")
1563   (let ((Info-history nil)
1564         (case-fold-search t))
1565     ;; Go to the last node in the menu of Top.
1566     (Info-goto-node (Info-extract-menu-counting nil))
1567     ;; If the last node in the menu is not last in pointer structure,
1568     ;; move forward until we can't go any farther.
1569     (while (Info-forward-node t t) nil)
1570     ;; Then keep moving down to last subnode, unless we reach an index.
1571     (while (and (not (string-match "\\<index\\>" Info-current-node))
1572                 (save-excursion (search-forward "\n* Menu:" nil t)))
1573       (Info-goto-node (Info-extract-menu-counting nil)))))
1574
1575 (defun Info-forward-node (&optional not-down no-error)
1576   "Go forward one node, considering all nodes as forming one sequence."
1577   (interactive)
1578   (goto-char (point-min))
1579   (forward-line 1)
1580   (let ((case-fold-search t))
1581     ;; three possibilities, in order of priority:
1582     ;;     1. next node is in a menu in this node (but not in an index)
1583     ;;     2. next node is next at same level
1584     ;;     3. next node is up and next
1585     (cond ((and (not not-down)
1586                 (save-excursion (search-forward "\n* menu:" nil t))
1587                 (not (string-match "\\<index\\>" Info-current-node)))
1588            (Info-goto-node (Info-extract-menu-counting 1))
1589            t)
1590           ((save-excursion
1591              (save-restriction
1592                (let (limit)
1593                  (when Info-header-line
1594                    (goto-char (point-min))
1595                    (widen)
1596                    (forward-line -1)
1597                    (setq limit (point))
1598                    (forward-line 1))
1599                  (search-backward "next:" limit t))))
1600            (Info-next)
1601            t)
1602           ((and (save-excursion
1603                   (save-restriction
1604                     (let (limit)
1605                       (when Info-header-line
1606                         (goto-char (point-min))
1607                         (widen)
1608                         (forward-line -1)
1609                         (setq limit (point))
1610                         (forward-line 1))
1611                       (search-backward "up:" limit t))))
1612                 ;; Use string-equal, not equal, to ignore text props.
1613                 (not (string-equal (downcase (Info-extract-pointer "up"))
1614                                    "top")))
1615            (let ((old-node Info-current-node))
1616              (Info-up)
1617              (let (Info-history success)
1618                (unwind-protect
1619                    (setq success (Info-forward-node t no-error))
1620                  (or success (Info-goto-node old-node))))))
1621           (no-error nil)
1622           (t (error "No pointer forward from this node")))))
1623
1624 (defun Info-backward-node ()
1625   "Go backward one node, considering all nodes as forming one sequence."
1626   (interactive)
1627   (let ((prevnode (Info-extract-pointer "prev[ious]*" t))
1628         (upnode (Info-extract-pointer "up" t))
1629         (case-fold-search t))
1630     (cond ((and upnode (string-match "(" upnode))
1631            (error "First node in file"))
1632           ((and upnode (or (null prevnode)
1633                            ;; Use string-equal, not equal,
1634                            ;; to ignore text properties.
1635                            (string-equal (downcase prevnode)
1636                                          (downcase upnode))))
1637            (Info-up))
1638           (prevnode
1639            ;; If we move back at the same level,
1640            ;; go down to find the last subnode*.
1641            (Info-prev)
1642            (let (Info-history)
1643              (while (and (not (string-match "\\<index\\>" Info-current-node))
1644                          (save-excursion (search-forward "\n* Menu:" nil t)))
1645                (Info-goto-node (Info-extract-menu-counting nil)))))
1646           (t
1647            (error "No pointer backward from this node")))))
1648
1649 (defun Info-exit ()
1650   "Exit Info by selecting some other buffer."
1651   (interactive)
1652   (if Info-standalone
1653       (save-buffers-kill-emacs)
1654     (quit-window)))
1655
1656 (defun Info-next-menu-item ()
1657   (interactive)
1658   ;; Bind this in case the user sets it to nil.
1659   (let* ((case-fold-search t)
1660          (node
1661           (save-excursion
1662             (forward-line -1)
1663             (search-forward "\n* menu:" nil t)
1664             (and (search-forward "\n* " nil t)
1665                  (Info-extract-menu-node-name)))))
1666     (if node (Info-goto-node node)
1667       (error "No more items in menu"))))
1668
1669 (defun Info-last-menu-item ()
1670   (interactive)
1671   (save-excursion
1672     (forward-line 1)
1673     ;; Bind this in case the user sets it to nil.
1674     (let* ((case-fold-search t)
1675            (beg (save-excursion
1676                   (and (search-backward "\n* menu:" nil t)
1677                        (point)))))
1678       (or (and beg (search-backward "\n* " beg t))
1679           (error "No previous items in menu")))
1680     (Info-goto-node (save-excursion
1681                       (goto-char (match-end 0))
1682                       (Info-extract-menu-node-name)))))
1683
1684 (defmacro Info-no-error (&rest body)
1685   (list 'condition-case nil (cons 'progn (append body '(t))) '(error nil)))
1686
1687 (defun Info-next-preorder ()
1688   "Go to the next subnode or the next node, or go up a level."
1689   (interactive)
1690   (cond ((Info-no-error (Info-next-menu-item)))
1691         ((Info-no-error (Info-next)))
1692         ((Info-no-error (Info-up t))
1693          ;; Since we have already gone thru all the items in this menu,
1694          ;; go up to the end of this node.
1695          (goto-char (point-max))
1696          ;; Since logically we are done with the node with that menu,
1697          ;; move on from it.
1698          (Info-next-preorder))
1699         (t
1700          (error "No more nodes"))))
1701
1702 (defun Info-last-preorder ()
1703   "Go to the last node, popping up a level if there is none."
1704   (interactive)
1705   (cond ((Info-no-error
1706           (Info-last-menu-item)
1707           ;; If we go down a menu item, go to the end of the node
1708           ;; so we can scroll back through it.
1709           (goto-char (point-max)))
1710          ;; Keep going down, as long as there are nested menu nodes.
1711          (while (Info-no-error
1712                  (Info-last-menu-item)
1713                  ;; If we go down a menu item, go to the end of the node
1714                  ;; so we can scroll back through it.
1715                  (goto-char (point-max))))
1716          (recenter -1))
1717         ((and (Info-no-error (Info-extract-pointer "prev"))
1718               (not (equal (Info-extract-pointer "up")
1719                           (Info-extract-pointer "prev"))))
1720          (Info-no-error (Info-prev))
1721          (goto-char (point-max))
1722          (while (Info-no-error
1723                  (Info-last-menu-item)
1724                  ;; If we go down a menu item, go to the end of the node
1725                  ;; so we can scroll back through it.
1726                  (goto-char (point-max))))
1727          (recenter -1))
1728         ((Info-no-error (Info-up t))
1729          (goto-char (point-min))
1730          (let ((case-fold-search t))
1731            (or (search-forward "\n* Menu:" nil t)
1732                (goto-char (point-max)))))
1733         (t (error "No previous nodes"))))
1734
1735 (defun Info-scroll-up ()
1736   "Scroll one screenful forward in Info, considering all nodes as one sequence.
1737 Once you scroll far enough in a node that its menu appears on the screen
1738 but after point, the next scroll moves into its first subnode, unless
1739 `Info-scroll-prefer-subnodes' is nil.
1740
1741 When you scroll past the end of a node, that goes to the next node if
1742 `Info-scroll-prefer-subnodes' is non-nil and to the first subnode otherwise;
1743 if this node has no successor, it moves to the parent node's successor,
1744 and so on.  If `Info-scroll-prefer-subnodes' is non-nil and point is inside
1745 the menu of a node, it moves to subnode indicated by the following menu
1746 item.  (That case won't normally result from this command, but can happen
1747 in other ways.)"
1748
1749   (interactive)
1750   (if (or (< (window-start) (point-min))
1751           (> (window-start) (point-max)))
1752       (set-window-start (selected-window) (point)))
1753   (let* ((case-fold-search t)
1754          (virtual-end (save-excursion
1755                         (goto-char (point-min))
1756                         (if (and Info-scroll-prefer-subnodes
1757                                  (search-forward "\n* Menu:" nil t))
1758                             (point)
1759                           (point-max)))))
1760     (if (or (< virtual-end (window-start))
1761             (pos-visible-in-window-p virtual-end))
1762         (cond
1763          (Info-scroll-prefer-subnodes (Info-next-preorder))
1764          ((Info-no-error (Info-goto-node (Info-extract-menu-counting 1))))
1765          (t (Info-next-preorder)))
1766       (scroll-up))))
1767
1768 (defun Info-scroll-down ()
1769   "Scroll one screenful back in Info, considering all nodes as one sequence.
1770 If point is within the menu of a node, and `Info-scroll-prefer-subnodes'
1771 is non-nil, this goes to its last subnode.  When you scroll past the
1772 beginning of a node, that goes to the previous node or back up to the
1773 parent node."
1774   (interactive)
1775   (if (or (< (window-start) (point-min))
1776           (> (window-start) (point-max)))
1777       (set-window-start (selected-window) (point)))
1778   (let* ((case-fold-search t)
1779          (current-point (point))
1780          (virtual-end
1781           (and Info-scroll-prefer-subnodes
1782                (save-excursion
1783                  (beginning-of-line)
1784                  (setq current-point (point))
1785                  (goto-char (point-min))
1786                  (search-forward "\n* Menu:"
1787                                  current-point
1788                                  t)))))
1789     (if (or virtual-end
1790             (pos-visible-in-window-p (point-min) nil t))
1791         (Info-last-preorder)
1792       (scroll-down))))
1793
1794 (defun Info-next-reference (&optional recur)
1795   "Move cursor to the next cross-reference or menu item in the node."
1796   (interactive)
1797   (let ((pat "\\*note[ \n\t]*\\([^:]*\\):\\|^\\* .*:")
1798         (old-pt (point))
1799         (case-fold-search t))
1800     (or (eobp) (forward-char 1))
1801     (or (re-search-forward pat nil t)
1802         (progn
1803           (goto-char (point-min))
1804           (or (re-search-forward pat nil t)
1805               (progn
1806                 (goto-char old-pt)
1807                 (error "No cross references in this node")))))
1808     (goto-char (match-beginning 0))
1809     (if (looking-at "\\* Menu:")
1810         (if recur
1811             (error "No cross references in this node")
1812           (Info-next-reference t)))))
1813
1814 (defun Info-prev-reference (&optional recur)
1815   "Move cursor to the previous cross-reference or menu item in the node."
1816   (interactive)
1817   (let ((pat "\\*note[ \n\t]*\\([^:]*\\):\\|^\\* .*:")
1818         (old-pt (point))
1819         (case-fold-search t))
1820     (or (re-search-backward pat nil t)
1821         (progn
1822           (goto-char (point-max))
1823           (or (re-search-backward pat nil t)
1824               (progn
1825                 (goto-char old-pt)
1826                 (error "No cross references in this node")))))
1827     (goto-char (match-beginning 0))
1828     (if (looking-at "\\* Menu:")
1829         (if recur
1830             (error "No cross references in this node")
1831           (Info-prev-reference t)))))
1832
1833 (defun Info-goto-index ()
1834   (Info-goto-node "Top")
1835   (or (search-forward "\n* menu:" nil t)
1836       (error "No index"))
1837   (or (re-search-forward "\n\\* \\(.*\\<Index\\>\\)" nil t)
1838       (error "No index"))
1839   (goto-char (match-beginning 1))
1840   ;; Protect Info-history so that the current node (Top) is not added to it.
1841   (let ((Info-history nil))
1842     (Info-goto-node (Info-extract-menu-node-name))))
1843
1844 (defun Info-index (topic)
1845   "Look up a string TOPIC in the index for this file.
1846 The index is defined as the first node in the top level menu whose
1847 name contains the word \"Index\", plus any immediately following
1848 nodes whose names also contain the word \"Index\".
1849 If there are no exact matches to the specified topic, this chooses
1850 the first match which is a case-insensitive substring of a topic.
1851 Use the `,' command to see the other matches.
1852 Give a blank topic name to go to the Index node itself."
1853   (interactive
1854    (list
1855     (let ((Info-complete-menu-buffer (clone-buffer))
1856           (Info-complete-next-re "\\<Index\\>"))
1857       (unwind-protect
1858           (with-current-buffer Info-complete-menu-buffer
1859             (Info-goto-index)
1860             (completing-read "Index topic: " 'Info-complete-menu-item))
1861         (kill-buffer Info-complete-menu-buffer)))))
1862   (let ((orignode Info-current-node)
1863         (rnode nil)
1864         (pattern (format "\n\\* +\\([^\n:]*%s[^\n:]*\\):[ \t]*\\([^.\n]*\\)\\.[ \t]*\\([0-9]*\\)"
1865                          (regexp-quote topic)))
1866         node
1867         (case-fold-search t))
1868     (Info-goto-index)
1869     (or (equal topic "")
1870         (let ((matches nil)
1871               (exact nil)
1872               ;; We bind Info-history to nil for internal node-switches so
1873               ;; that we don't put junk in the history.  In the first
1874               ;; Info-goto-index call, above, we do update the history
1875               ;; because that is what the user's previous node choice into it.
1876               (Info-history nil)
1877               found)
1878           (while
1879               (progn
1880                 (goto-char (point-min))
1881                 (while (re-search-forward pattern nil t)
1882                   (push (list (match-string-no-properties 1)
1883                               (match-string-no-properties 2)
1884                               Info-current-node
1885                               (string-to-int (concat "0"
1886                                                      (match-string 3))))
1887                         matches))
1888                 (and (setq node (Info-extract-pointer "next" t))
1889                      (string-match "\\<Index\\>" node)))
1890             (Info-goto-node node))
1891           (or matches
1892               (progn
1893                 (Info-goto-node orignode)
1894                 (error "No `%s' in index" topic)))
1895           ;; Here it is a feature that assoc is case-sensitive.
1896           (while (setq found (assoc topic matches))
1897             (setq exact (cons found exact)
1898                   matches (delq found matches)))
1899           (setq Info-index-alternatives (nconc exact (nreverse matches)))
1900           (Info-index-next 0)))))
1901
1902 (defun Info-index-next (num)
1903   "Go to the next matching index item from the last `i' command."
1904   (interactive "p")
1905   (or Info-index-alternatives
1906       (error "No previous `i' command"))
1907   (while (< num 0)
1908     (setq num (+ num (length Info-index-alternatives))))
1909   (while (> num 0)
1910     (setq Info-index-alternatives
1911           (nconc (cdr Info-index-alternatives)
1912                  (list (car Info-index-alternatives)))
1913           num (1- num)))
1914   (Info-goto-node (nth 1 (car Info-index-alternatives)))
1915   (if (> (nth 3 (car Info-index-alternatives)) 0)
1916       (forward-line (nth 3 (car Info-index-alternatives)))
1917     (forward-line 3)                    ; don't search in headers
1918     (let ((name (car (car Info-index-alternatives))))
1919       (Info-find-index-name name)))
1920   (message "Found `%s' in %s.  %s"
1921            (car (car Info-index-alternatives))
1922            (nth 2 (car Info-index-alternatives))
1923            (if (cdr Info-index-alternatives)
1924                "(Press `,' for more)"
1925              "(Only match)")))
1926
1927 (defun Info-find-index-name (name)
1928   "Move point to the place within the current node where NAME is defined."
1929   (let ((case-fold-search t))
1930     (if (or (re-search-forward (format
1931                                 "[a-zA-Z]+: %s\\( \\|$\\)"
1932                                 (regexp-quote name)) nil t)
1933             (search-forward (format "`%s'" name) nil t)
1934             (and (string-match "\\`.*\\( (.*)\\)\\'" name)
1935                  (search-forward
1936                   (format "`%s'" (substring name 0 (match-beginning 1)))
1937                   nil t))
1938             (search-forward name nil t))
1939         (beginning-of-line)
1940       (goto-char (point-min)))))
1941
1942 (defun Info-undefined ()
1943   "Make command be undefined in Info."
1944   (interactive)
1945   (ding))
1946
1947 (defun Info-help ()
1948   "Enter the Info tutorial."
1949   (interactive)
1950   (delete-other-windows)
1951   (Info-find-node "info"
1952                   (if (< (window-height) 23)
1953                       "Help-Small-Screen"
1954                     "Help")))
1955
1956 (defun Info-summary ()
1957   "Display a brief summary of all Info commands."
1958   (interactive)
1959   (save-window-excursion
1960     (switch-to-buffer "*Help*")
1961     (setq buffer-read-only nil)
1962     (erase-buffer)
1963     (insert (documentation 'Info-mode))
1964     (help-mode)
1965     (goto-char (point-min))
1966     (let (ch flag)
1967       (while (progn (setq flag (not (pos-visible-in-window-p (point-max))))
1968                     (message (if flag "Type Space to see more"
1969                                "Type Space to return to Info"))
1970                     (if (not (eq ?\  (setq ch (read-event))))
1971                         (progn (setq unread-command-events (list ch)) nil)
1972                       flag))
1973         (scroll-up)))
1974     (bury-buffer "*Help*")))
1975 \f
1976 (defun Info-get-token (pos start all &optional errorstring)
1977   "Return the token around POS.
1978 POS must be somewhere inside the token
1979 START is a regular expression which will match the
1980     beginning of the tokens delimited string
1981 ALL is a regular expression with a single
1982     parenthesized subpattern which is the token to be
1983     returned.  E.g. '{\(.*\)}' would return any string
1984     enclosed in braces around POS.
1985 ERRORSTRING optional fourth argument, controls action on no match
1986     nil: return nil
1987     t: beep
1988     a string: signal an error, using that string."
1989   (let ((case-fold-search t))
1990     (save-excursion
1991       (goto-char pos)
1992       ;; First look for a match for START that goes across POS.
1993       (while (and (not (bobp)) (> (point) (- pos (length start)))
1994                   (not (looking-at start)))
1995         (forward-char -1))
1996       ;; If we did not find one, search back for START
1997       ;; (this finds only matches that end at or before POS).
1998       (or (looking-at start)
1999           (progn
2000             (goto-char pos)
2001             (re-search-backward start (max (point-min) (- pos 200)) 'yes)))
2002       (let (found)
2003         (while (and (re-search-forward all (min (point-max) (+ pos 200)) 'yes)
2004                     (not (setq found (and (<= (match-beginning 0) pos)
2005                                           (> (match-end 0) pos))))))
2006         (if (and found (<= (match-beginning 0) pos)
2007                  (> (match-end 0) pos))
2008             (match-string-no-properties 1)
2009           (cond ((null errorstring)
2010                  nil)
2011                 ((eq errorstring t)
2012                  (beep)
2013                  nil)
2014                 (t
2015                  (error "No %s around position %d" errorstring pos))))))))
2016
2017 (defun Info-mouse-follow-nearest-node (click)
2018   "\\<Info-mode-map>Follow a node reference near point.
2019 Like \\[Info-menu], \\[Info-follow-reference], \\[Info-next], \\[Info-prev] or \\[Info-up] command, depending on where you click.
2020 At end of the node's text, moves to the next node, or up if none."
2021   (interactive "e")
2022   (mouse-set-point click)
2023   (and (not (Info-try-follow-nearest-node))
2024        (save-excursion (forward-line 1) (eobp))
2025        (Info-next-preorder)))
2026
2027 (defun Info-follow-nearest-node ()
2028   "\\<Info-mode-map>Follow a node reference near point.
2029 Like \\[Info-menu], \\[Info-follow-reference], \\[Info-next], \\[Info-prev] or \\[Info-up] command, depending on where point is.
2030 If no reference to follow, moves to the next node, or up if none."
2031   (interactive)
2032   (or (Info-try-follow-nearest-node)
2033       (Info-next-preorder)))
2034
2035 ;; Common subroutine.
2036 (defun Info-try-follow-nearest-node ()
2037   "Follow a node reference near point.  Return non-nil if successful."
2038   (let (node)
2039     (cond
2040      ((setq node (Info-get-token (point) "\\*note[ \n]"
2041                                  "\\*note[ \n]\\([^:]*\\):"))
2042       (Info-follow-reference node))
2043      ((setq node (Info-get-token (point) "\\* +" "\\* +\\([^:]*\\)::"))
2044       (Info-goto-node node))
2045      ((Info-get-token (point) "\\* +" "\\* +\\([^:]*\\):")
2046       (beginning-of-line)
2047       (forward-char 2)
2048       (setq node (Info-extract-menu-node-name))
2049       (Info-goto-node node))
2050      ((setq node (Info-get-token (point) "Up: " "Up: \\([^,\n\t]*\\)"))
2051       (Info-goto-node node))
2052      ((setq node (Info-get-token (point) "Next: " "Next: \\([^,\n\t]*\\)"))
2053       (Info-goto-node node))
2054      ((setq node (Info-get-token (point) "File: " "File: \\([^,\n\t]*\\)"))
2055       (Info-goto-node "Top"))
2056      ((setq node (Info-get-token (point) "Prev: " "Prev: \\([^,\n\t]*\\)"))
2057       (Info-goto-node node)))
2058     node))
2059 \f
2060 (defvar Info-mode-map nil
2061   "Keymap containing Info commands.")
2062 (if Info-mode-map
2063     nil
2064   (setq Info-mode-map (make-keymap))
2065   (suppress-keymap Info-mode-map)
2066   (define-key Info-mode-map "." 'beginning-of-buffer)
2067   (define-key Info-mode-map " " 'Info-scroll-up)
2068   (define-key Info-mode-map "\C-m" 'Info-follow-nearest-node)
2069   (define-key Info-mode-map "\t" 'Info-next-reference)
2070   (define-key Info-mode-map "\e\t" 'Info-prev-reference)
2071   (define-key Info-mode-map "1" 'Info-nth-menu-item)
2072   (define-key Info-mode-map "2" 'Info-nth-menu-item)
2073   (define-key Info-mode-map "3" 'Info-nth-menu-item)
2074   (define-key Info-mode-map "4" 'Info-nth-menu-item)
2075   (define-key Info-mode-map "5" 'Info-nth-menu-item)
2076   (define-key Info-mode-map "6" 'Info-nth-menu-item)
2077   (define-key Info-mode-map "7" 'Info-nth-menu-item)
2078   (define-key Info-mode-map "8" 'Info-nth-menu-item)
2079   (define-key Info-mode-map "9" 'Info-nth-menu-item)
2080   (define-key Info-mode-map "0" 'undefined)
2081   (define-key Info-mode-map "?" 'Info-summary)
2082   (define-key Info-mode-map "]" 'Info-forward-node)
2083   (define-key Info-mode-map "[" 'Info-backward-node)
2084   (define-key Info-mode-map "<" 'Info-top-node)
2085   (define-key Info-mode-map ">" 'Info-final-node)
2086   (define-key Info-mode-map "b" 'beginning-of-buffer)
2087   (define-key Info-mode-map "c" 'Info-copy-current-node-name)
2088   (define-key Info-mode-map "d" 'Info-directory)
2089   (define-key Info-mode-map "e" 'Info-edit)
2090   (define-key Info-mode-map "f" 'Info-follow-reference)
2091   (define-key Info-mode-map "g" 'Info-goto-node)
2092   (define-key Info-mode-map "h" 'Info-help)
2093   (define-key Info-mode-map "i" 'Info-index)
2094   (define-key Info-mode-map "l" 'Info-last)
2095   (define-key Info-mode-map "m" 'Info-menu)
2096   (define-key Info-mode-map "n" 'Info-next)
2097   (define-key Info-mode-map "p" 'Info-prev)
2098   (define-key Info-mode-map "q" 'Info-exit)
2099   (define-key Info-mode-map "s" 'Info-search)
2100   ;; For consistency with Rmail.
2101   (define-key Info-mode-map "\M-s" 'Info-search)
2102   (define-key Info-mode-map "\M-n" 'clone-buffer)
2103   (define-key Info-mode-map "t" 'Info-top-node)
2104   (define-key Info-mode-map "u" 'Info-up)
2105   (define-key Info-mode-map "," 'Info-index-next)
2106   (define-key Info-mode-map "\177" 'Info-scroll-down)
2107   (define-key Info-mode-map [mouse-2] 'Info-mouse-follow-nearest-node)
2108   )
2109
2110 (defun Info-check-pointer (item)
2111   "Non-nil if ITEM is present in this node."
2112   (condition-case nil
2113       (Info-extract-pointer item)
2114     (error nil)))
2115
2116 (easy-menu-define
2117  Info-mode-menu Info-mode-map
2118  "Menu for info files."
2119  '("Info"
2120    ["Up" Info-up :active (Info-check-pointer "up")
2121     :help "Go up in the Info tree"]
2122    ["Next" Info-next :active (Info-check-pointer "next")
2123     :help "Go to the next node"]
2124    ["Previous" Info-prev :active (Info-check-pointer "prev[ious]*")
2125     :help "Go to the previous node"]
2126    ["Backward" Info-backward-node
2127     :help "Go backward one node, considering all as a sequence"]
2128    ["Forward" Info-forward-node
2129     :help "Go forward one node, considering all as a sequence"]
2130    ["Beginning" beginning-of-buffer
2131     :help "Go to beginning of this node"]
2132    ["Top" Info-top-node
2133     :help "Go to top node of file"]
2134    ["Final Node" Info-final-node
2135     :help "Go to final node in this file"]
2136    ("Menu Item" ["You should never see this" report-emacs-bug t])
2137    ("Reference" ["You should never see this" report-emacs-bug t])
2138    ["Search..." Info-search
2139     :help "Search for regular expression in this Info file"]
2140    ["Go to Node..." Info-goto-node
2141     :help "Go to a named node"]
2142    ["Last" Info-last :active Info-history
2143     :help "Go to the last node you were at"]
2144    ("Index..."
2145     ["Lookup a String" Info-index
2146      :help "Look for a string in the index items"]
2147     ["Next Matching Item" Info-index-next
2148      :help "Look for another occurrence of previous item"])
2149    ["Edit" Info-edit :help "Edit contents of this node"
2150     :active Info-enable-edit]
2151    ["Copy Node Name" Info-copy-current-node-name
2152     :help "Copy the name of the current node into the kill ring"]
2153    ["Exit" Info-exit :help "Stop reading Info"]))
2154
2155
2156 (defvar info-tool-bar-map
2157   (if (display-graphic-p)
2158       (let ((map (make-sparse-keymap)))
2159         (tool-bar-local-item-from-menu 'Info-exit "close" map Info-mode-map)
2160         (tool-bar-local-item-from-menu 'Info-prev "left_arrow" map Info-mode-map)
2161         (tool-bar-local-item-from-menu 'Info-next "right_arrow" map Info-mode-map)
2162         (tool-bar-local-item-from-menu 'Info-up "up_arrow" map Info-mode-map)
2163         (tool-bar-local-item-from-menu 'Info-last "undo" map Info-mode-map)
2164         (tool-bar-local-item-from-menu 'Info-top-node "home" map Info-mode-map)
2165         (tool-bar-local-item-from-menu 'Info-index "index" map Info-mode-map)
2166         (tool-bar-local-item-from-menu 'Info-goto-node "jump_to" map Info-mode-map)
2167         (tool-bar-local-item-from-menu 'Info-search "search" map Info-mode-map)
2168         map)))
2169
2170 (defvar Info-menu-last-node nil)
2171 ;; Last node the menu was created for.
2172 ;; Value is a list, (FILE-NAME NODE-NAME).
2173
2174 (defun Info-menu-update ()
2175   "Update the Info menu for the current node."
2176   (condition-case nil
2177       (if (or (not (eq major-mode 'Info-mode))
2178               (equal (list Info-current-file Info-current-node)
2179                      Info-menu-last-node))
2180           ()
2181         ;; Update menu menu.
2182         (let* ((Info-complete-menu-buffer (current-buffer))
2183                (items (nreverse (condition-case nil
2184                                     (Info-complete-menu-item "" nil t)
2185                                   (error nil))))
2186                entries current
2187                (number 0))
2188           (while (and items (< number 9))
2189             (setq current (car items)
2190                   items (cdr items)
2191                   number (1+ number))
2192             (setq entries (cons `[,current
2193                                   (Info-menu ,current)
2194                                   :keys ,(format "%d" number)]
2195                                 entries)))
2196           (if items
2197               (setq entries (cons ["Other..." Info-menu t] entries)))
2198           (or entries
2199               (setq entries (list ["No menu" nil nil] nil :active)))
2200           (easy-menu-change '("Info") "Menu Item" (nreverse entries)))
2201         ;; Update reference menu.  Code stolen from `Info-follow-reference'.
2202         (let ((items nil)
2203               str i entries current
2204               (number 0)
2205               (case-fold-search t))
2206           (save-excursion
2207             (goto-char (point-min))
2208             (while (re-search-forward "\\*note[ \n\t]*\\([^:]*\\):" nil t)
2209               (setq str (buffer-substring
2210                          (match-beginning 1)
2211                          (1- (point))))
2212               (setq i 0)
2213               (while (setq i (string-match "[ \n\t]+" str i))
2214                 (setq str (concat (substring str 0 i) " "
2215                                   (substring str (match-end 0))))
2216                 (setq i (1+ i)))
2217               (setq items
2218                     (cons str items))))
2219           (while (and items (< number 9))
2220             (setq current (car items)
2221                   items (cdr items)
2222                   number (1+ number))
2223             (setq entries (cons `[,current
2224                                   (Info-follow-reference ,current)
2225                                   t]
2226                                 entries)))
2227           (if items
2228               (setq entries (cons ["Other..." Info-follow-reference t]
2229                                   entries)))
2230           (or entries
2231               (setq entries (list ["No references" nil nil] nil :active)))
2232           (easy-menu-change '("Info") "Reference" (nreverse entries)))
2233         ;; Update last seen node.
2234         (setq Info-menu-last-node (list Info-current-file Info-current-node)))
2235     ;; Try to avoid entering infinite beep mode in case of errors.
2236     (error (ding))))
2237
2238 \f
2239 (defun Info-copy-current-node-name ()
2240   "Put the name of the current info node into the kill ring.
2241 The name of the info file is prepended to the node name in parentheses."
2242   (interactive)
2243   (unless Info-current-node
2244     (error "No current info node"))
2245   (kill-new
2246    (concat "("
2247            (file-name-nondirectory
2248             (if (stringp Info-current-file)
2249                 Info-current-file
2250               (or buffer-file-name "")))
2251            ")"
2252            Info-current-node)))
2253
2254 \f
2255 ;; Info mode is suitable only for specially formatted data.
2256 (put 'Info-mode 'mode-class 'special)
2257 (put 'Info-mode 'no-clone-indirect t)
2258
2259 (defun Info-mode ()
2260   "Info mode provides commands for browsing through the Info documentation tree.
2261 Documentation in Info is divided into \"nodes\", each of which discusses
2262 one topic and contains references to other nodes which discuss related
2263 topics.  Info has commands to follow the references and show you other nodes.
2264
2265 \\<Info-mode-map>\
2266 \\[Info-help]   Invoke the Info tutorial.
2267 \\[Info-exit]   Quit Info: reselect previously selected buffer.
2268
2269 Selecting other nodes:
2270 \\[Info-mouse-follow-nearest-node]
2271         Follow a node reference you click on.
2272           This works with menu items, cross references, and
2273           the \"next\", \"previous\" and \"up\", depending on where you click.
2274 \\[Info-follow-nearest-node]    Follow a node reference near point, like \\[Info-mouse-follow-nearest-node].
2275 \\[Info-next]   Move to the \"next\" node of this node.
2276 \\[Info-prev]   Move to the \"previous\" node of this node.
2277 \\[Info-up]     Move \"up\" from this node.
2278 \\[Info-menu]   Pick menu item specified by name (or abbreviation).
2279           Picking a menu item causes another node to be selected.
2280 \\[Info-directory]      Go to the Info directory node.
2281 \\[Info-follow-reference]       Follow a cross reference.  Reads name of reference.
2282 \\[Info-last]   Move to the last node you were at.
2283 \\[Info-index]  Look up a topic in this file's Index and move to that node.
2284 \\[Info-index-next]     (comma) Move to the next match from a previous `i' command.
2285 \\[Info-top-node]       Go to the Top node of this file.
2286 \\[Info-final-node]     Go to the final node in this file.
2287 \\[Info-backward-node]  Go backward one node, considering all nodes as forming one sequence.
2288 \\[Info-forward-node]   Go forward one node, considering all nodes as forming one sequence.
2289
2290 Moving within a node:
2291 \\[Info-scroll-up]      Normally, scroll forward a full screen.
2292           Once you scroll far enough in a node that its menu appears on the
2293           screen but after point, the next scroll moves into its first
2294           subnode.  When after all menu items (or if there is no menu),
2295           move up to the parent node.
2296 \\[Info-scroll-down]    Normally, scroll backward.  If the beginning of the buffer is
2297           already visible, try to go to the previous menu entry, or up
2298           if there is none.
2299 \\[beginning-of-buffer] Go to beginning of node.
2300
2301 Advanced commands:
2302 \\[Info-exit]   Quit Info: reselect previously selected buffer.
2303 \\[Info-edit]   Edit contents of selected node.
2304 1       Pick first item in node's menu.
2305 2, 3, 4, 5   Pick second ... fifth item in node's menu.
2306 \\[Info-goto-node]      Move to node specified by name.
2307           You may include a filename as well, as (FILENAME)NODENAME.
2308 \\[universal-argument] \\[info] Move to new Info file with completion.
2309 \\[Info-search] Search through this Info file for specified regexp,
2310           and select the node in which the next occurrence is found.
2311 \\[Info-next-reference] Move cursor to next cross-reference or menu item.
2312 \\[Info-prev-reference] Move cursor to previous cross-reference or menu item."
2313   (kill-all-local-variables)
2314   (setq major-mode 'Info-mode)
2315   (setq mode-name "Info")
2316   (setq tab-width 8)
2317   (use-local-map Info-mode-map)
2318   (add-hook 'activate-menubar-hook 'Info-menu-update nil t)
2319   (set-syntax-table text-mode-syntax-table)
2320   (setq local-abbrev-table text-mode-abbrev-table)
2321   (setq case-fold-search t)
2322   (setq buffer-read-only t)
2323   (make-local-variable 'Info-current-file)
2324   (make-local-variable 'Info-current-subfile)
2325   (make-local-variable 'Info-current-node)
2326   (make-local-variable 'Info-tag-table-marker)
2327   (setq Info-tag-table-marker (make-marker))
2328   (make-local-variable 'Info-tag-table-buffer)
2329   (setq Info-tag-table-buffer nil)
2330   (make-local-variable 'Info-history)
2331   (make-local-variable 'Info-index-alternatives)
2332   (make-local-variable 'Info-header-line)
2333   (set (make-local-variable 'tool-bar-map) info-tool-bar-map)
2334   ;; This is for the sake of the invisible text we use handling titles.
2335   (make-local-variable 'line-move-ignore-invisible)
2336   (setq line-move-ignore-invisible t)
2337   (add-hook 'clone-buffer-hook 'Info-clone-buffer-hook nil t)
2338   (Info-set-mode-line)
2339   (run-hooks 'Info-mode-hook))
2340
2341 (defun Info-clone-buffer-hook ()
2342   (when (bufferp Info-tag-table-buffer)
2343     (setq Info-tag-table-buffer
2344           (with-current-buffer Info-tag-table-buffer (clone-buffer))))
2345   (let ((m Info-tag-table-marker))
2346     (when (markerp m)
2347       (setq Info-tag-table-marker
2348             (if (and (marker-position m) (bufferp Info-tag-table-buffer))
2349                 (with-current-buffer Info-tag-table-buffer
2350                   (copy-marker (marker-position m)))
2351               (make-marker))))))
2352
2353 (defvar Info-edit-map (let ((map (make-sparse-keymap)))
2354                         (set-keymap-parent map text-mode-map)
2355                         (define-key map "\C-c\C-c" 'Info-cease-edit)
2356                         map)
2357   "Local keymap used within `e' command of Info.")
2358
2359 ;; Info-edit mode is suitable only for specially formatted data.
2360 (put 'Info-edit-mode 'mode-class 'special)
2361
2362 (defun Info-edit-mode ()
2363   "Major mode for editing the contents of an Info node.
2364 Like text mode with the addition of `Info-cease-edit'
2365 which returns to Info mode for browsing.
2366 \\{Info-edit-map}"
2367   (use-local-map Info-edit-map)
2368   (setq major-mode 'Info-edit-mode)
2369   (setq mode-name "Info Edit")
2370   (kill-local-variable 'mode-line-buffer-identification)
2371   (setq buffer-read-only nil)
2372   (force-mode-line-update)
2373   (buffer-enable-undo (current-buffer))
2374   (run-hooks 'Info-edit-mode-hook))
2375
2376 (defun Info-edit ()
2377   "Edit the contents of this Info node.
2378 Allowed only if variable `Info-enable-edit' is non-nil."
2379   (interactive)
2380   (or Info-enable-edit
2381       (error "Editing info nodes is not enabled"))
2382   (Info-edit-mode)
2383   (message "%s" (substitute-command-keys
2384                  "Editing: Type \\<Info-edit-map>\\[Info-cease-edit] to return to info")))
2385
2386 (defun Info-cease-edit ()
2387   "Finish editing Info node; switch back to Info proper."
2388   (interactive)
2389   ;; Do this first, so nothing has changed if user C-g's at query.
2390   (and (buffer-modified-p)
2391        (y-or-n-p "Save the file? ")
2392        (save-buffer))
2393   (use-local-map Info-mode-map)
2394   (setq major-mode 'Info-mode)
2395   (setq mode-name "Info")
2396   (Info-set-mode-line)
2397   (setq buffer-read-only t)
2398   (force-mode-line-update)
2399   (and (marker-position Info-tag-table-marker)
2400        (buffer-modified-p)
2401        (message "Tags may have changed.  Use Info-tagify if necessary")))
2402 \f
2403 (defvar Info-file-list-for-emacs
2404   '("ediff" "eudc" "forms" "gnus" "info" ("mh" . "mh-e")
2405     "sc" "message" ("dired" . "dired-x") "viper" "vip" "idlwave"
2406     ("c" . "ccmode") ("c++" . "ccmode") ("objc" . "ccmode")
2407     ("java" . "ccmode") ("idl" . "ccmode") ("pike" . "ccmode")
2408     ("skeleton" . "autotype") ("auto-insert" . "autotype")
2409     ("copyright" . "autotype") ("executable" . "autotype")
2410     ("time-stamp" . "autotype") ("quickurl" . "autotype")
2411     ("tempo" . "autotype") ("hippie-expand" . "autotype")
2412     ("cvs" . "pcl-cvs") ("ada" . "ada-mode") "calc"
2413     ("calcAlg" . "calc") ("calcDigit" . "calc") ("calcVar" . "calc")
2414     "ebrowse" "eshell" "cl" "reftex" "speedbar" "widget" "woman"
2415     ("mail-header" . "emacs-mime") ("mail-content" . "emacs-mime")
2416     ("mail-encode" . "emacs-mime") ("mail-decode" . "emacs-mime")
2417     ("rfc2045" . "emacs-mime")
2418     ("rfc2231" . "emacs-mime")  ("rfc2047" . "emacs-mime")
2419     ("rfc2045" . "emacs-mime") ("rfc1843" . "emacs-mime")
2420     ("ietf-drums" . "emacs-mime")  ("quoted-printable" . "emacs-mime")
2421     ("binhex" . "emacs-mime") ("uudecode" . "emacs-mime")
2422     ("mailcap" . "emacs-mime") ("mm" . "emacs-mime")
2423     ("mml" . "emacs-mime"))
2424   "List of Info files that describe Emacs commands.
2425 An element can be a file name, or a list of the form (PREFIX . FILE)
2426 where PREFIX is a name prefix and FILE is the file to look in.
2427 If the element is just a file name, the file name also serves as the prefix.")
2428
2429 (defun Info-find-emacs-command-nodes (command)
2430   "Return a list of locations documenting COMMAND.
2431 The `info-file' property of COMMAND says which Info manual to search.
2432 If COMMAND has no property, the variable `Info-file-list-for-emacs'
2433 defines heuristics for which Info manual to try.
2434 The locations are of the format used in `Info-history', i.e.
2435 \(FILENAME NODENAME BUFFERPOS\)."
2436   (let ((where '())
2437         (cmd-desc (concat "^\\* +" (regexp-quote (symbol-name command))
2438                           "\\( <[0-9]+>\\)?:\\s *\\(.*\\)\\.$"))
2439         (info-file "emacs"))            ;default
2440     ;; Determine which info file this command is documented in.
2441     (if (get command 'info-file)
2442         (setq info-file (get command 'info-file))
2443       ;; If it doesn't say explicitly, test its name against
2444       ;; various prefixes that we know.
2445       (let ((file-list Info-file-list-for-emacs))
2446         (while file-list
2447           (let* ((elt (car file-list))
2448                  (name (if (consp elt)
2449                            (car elt)
2450                          elt))
2451                  (file (if (consp elt) (cdr elt) elt))
2452                  (regexp (concat "\\`" (regexp-quote name)
2453                                  "\\(\\'\\|-\\)")))
2454             (if (string-match regexp (symbol-name command))
2455                 (setq info-file file file-list nil))
2456             (setq file-list (cdr file-list))))))
2457     (Info-find-node info-file "Top")
2458     (or (and (search-forward "\n* menu:" nil t)
2459              (re-search-forward "\n\\* \\(.*\\<Index\\>\\)" nil t))
2460         (error "Info file `%s' appears to lack an index" info-file))
2461     (goto-char (match-beginning 1))
2462     ;; Bind Info-history to nil, to prevent the index nodes from
2463     ;; getting into the node history.
2464     (let ((Info-history nil)
2465           (exact nil)
2466           node found)
2467       (Info-goto-node (Info-extract-menu-node-name))
2468       (while
2469           (progn
2470             (goto-char (point-min))
2471             (while (re-search-forward cmd-desc nil t)
2472               (setq where
2473                     (cons (list Info-current-file
2474                                 (match-string-no-properties 2)
2475                                 0)
2476                           where)))
2477             (and (setq node (Info-extract-pointer "next" t))
2478                  (string-match "\\<Index\\>" node)))
2479         (Info-goto-node node)))
2480     where))
2481
2482 ;;;###autoload
2483 (defun Info-goto-emacs-command-node (command)
2484   "Go to the Info node in the Emacs manual for command COMMAND.
2485 The command is found by looking up in Emacs manual's indices
2486 or in another manual found via COMMAND's `info-file' property or
2487 the variable `Info-file-list-for-emacs'."
2488   (interactive "CFind documentation for command: ")
2489   (or (commandp command)
2490       (signal 'wrong-type-argument (list 'commandp command)))
2491   (let ((where (Info-find-emacs-command-nodes command)))
2492     (if where
2493         (let ((num-matches (length where)))
2494           ;; Get Info running, and pop to it in another window.
2495           (save-window-excursion
2496             (info))
2497           ;; FIXME It would be cool if this could use a buffer other
2498           ;; than *info*.
2499           (pop-to-buffer "*info*")
2500           ;; Bind Info-history to nil, to prevent the last Index node
2501           ;; visited by Info-find-emacs-command-nodes from being
2502           ;; pushed onto the history.
2503           (let ((Info-history nil))
2504             (Info-find-node (car (car where))
2505                             (car (cdr (car where)))))
2506           (if (> num-matches 1)
2507               (progn
2508                 ;; (car where) will be pushed onto Info-history
2509                 ;; when/if they go to another node.  Put the other
2510                 ;; nodes that were found on the history.
2511                 (setq Info-history (nconc (cdr where) Info-history))
2512                 (message "Found %d other entr%s.  Use %s to see %s."
2513                          (1- num-matches)
2514                          (if (> num-matches 2) "ies" "y")
2515                          (substitute-command-keys "\\[Info-last]")
2516                          (if (> num-matches 2) "them" "it")))))
2517       (error "Couldn't find documentation for %s" command))))
2518
2519 ;;;###autoload
2520 (defun Info-goto-emacs-key-command-node (key)
2521   "Go to the node in the Emacs manual which describes the command bound to KEY.
2522 KEY is a string.
2523 Interactively, if the binding is `execute-extended-command', a command is read.
2524 The command is found by looking up in Emacs manual's indices
2525 or in another manual found via COMMAND's `info-file' property or
2526 the variable `Info-file-list-for-emacs'."
2527   (interactive "kFind documentation for key: ")
2528   (let ((command (key-binding key)))
2529     (cond ((null command)
2530            (message "%s is undefined" (key-description key)))
2531           ((and (interactive-p)
2532                 (eq command 'execute-extended-command))
2533            (Info-goto-emacs-command-node
2534             (read-command "Find documentation for command: ")))
2535           (t
2536            (Info-goto-emacs-command-node command)))))
2537 \f
2538 (defface Info-title-1-face
2539   '((((type tty pc) (class color)) (:foreground "yellow" :weight bold))
2540     (t (:height 1.2 :inherit Info-title-2-face)))
2541   "Face for Info titles at level 1."
2542   :group 'info)
2543
2544 (defface Info-title-2-face
2545   '((((type tty pc) (class color)) (:foreground "lightblue" :weight bold))
2546     (t (:height 1.2 :inherit Info-title-3-face)))
2547   "Face for Info titles at level 2."
2548   :group 'info)
2549
2550 (defface Info-title-3-face
2551   '((((type tty pc) (class color)) (:weight bold))
2552     (t (:height 1.2 :inherit Info-title-4-face)))
2553   "Face for Info titles at level 3."
2554   :group 'info)
2555
2556 (defface Info-title-4-face
2557   '((((type tty pc) (class color)) (:weight bold))
2558     (t (:weight bold :inherit variable-pitch)))
2559   "Face for Info titles at level 4."
2560   :group 'info)
2561
2562 (defface info-menu-header
2563   '((((type tty pc))
2564      :underline t
2565      :weight bold)
2566     (t
2567      :inherit variable-pitch
2568      :weight bold))
2569   "Face for headers in Info menus."
2570   :group 'info)
2571
2572 (defun Info-fontify-menu-headers ()
2573   "Add the face `info-menu-header' to any header before a menu entry."
2574   (save-excursion
2575     (goto-char (point-min))
2576     (when (re-search-forward "\\* Menu:" nil t)
2577       (put-text-property (match-beginning 0) (match-end 0)
2578                          'font-lock-face 'info-menu-header)
2579       (while (re-search-forward "\n\n\\([^*\n ].*\\)\n\n?[*]" nil t)
2580         (put-text-property (match-beginning 1) (match-end 1)
2581                            'font-lock-face 'info-menu-header)))))
2582
2583 (defvar Info-next-link-keymap
2584   (let ((keymap (make-sparse-keymap)))
2585     (define-key keymap [header-line mouse-1] 'Info-next)
2586     (define-key keymap [header-line mouse-2] 'Info-next)
2587     (define-key keymap [header-line down-mouse-1] 'ignore)
2588     (define-key keymap [mouse-2] 'Info-next)
2589     keymap)
2590   "Keymap to put on the Next link in the text or the header line.")
2591
2592 (defvar Info-prev-link-keymap
2593   (let ((keymap (make-sparse-keymap)))
2594     (define-key keymap [header-line mouse-1] 'Info-prev)
2595     (define-key keymap [header-line mouse-2] 'Info-prev)
2596     (define-key keymap [header-line down-mouse-1] 'ignore)
2597     (define-key keymap [mouse-2] 'Info-prev)
2598     keymap)
2599   "Keymap to put on the Prev link in the text or the header line.")
2600
2601
2602 (defvar Info-up-link-keymap
2603   (let ((keymap (make-sparse-keymap)))
2604     (define-key keymap [header-line mouse-1] 'Info-up)
2605     (define-key keymap [header-line mouse-2] 'Info-up)
2606     (define-key keymap [header-line down-mouse-1] 'ignore)
2607     (define-key keymap [mouse-2] 'Info-up)
2608     keymap)
2609   "Keymap to put on the Up link in the text or the header line.")
2610
2611 (defun Info-fontify-node ()
2612   ;; Only fontify the node if it hasn't already been done.  [We pass in
2613   ;; LIMIT arg to `next-property-change' because it seems to search past
2614   ;; (point-max).]
2615   (unless (< (next-property-change (point-min) nil (point-max))
2616              (point-max))
2617     (save-excursion
2618       (let ((buffer-read-only nil)
2619             (case-fold-search t))
2620         (goto-char (point-min))
2621         (when (looking-at "^File: [^,: \t]+,?[ \t]+")
2622           (goto-char (match-end 0))
2623           (while (looking-at "[ \t]*\\([^:, \t\n]+\\):[ \t]+\\([^:,\t\n]+\\),?")
2624             (goto-char (match-end 0))
2625             (let* ((nbeg (match-beginning 2))
2626                    (nend (match-end 2))
2627                    (tbeg (match-beginning 1))
2628                    (tag (buffer-substring tbeg (match-end 1))))
2629               (if (string-equal tag "Node")
2630                   (put-text-property nbeg nend 'font-lock-face 'info-header-node)
2631                 (put-text-property nbeg nend 'font-lock-face 'info-header-xref)
2632                 (put-text-property tbeg nend 'mouse-face 'highlight)
2633                 (put-text-property tbeg nend
2634                                    'help-echo
2635                                    (concat "Go to node "
2636                                            (buffer-substring nbeg nend)))
2637                 ;; Always set up the text property keymap.
2638                 ;; It will either be used in the buffer
2639                 ;; or copied in the header line.
2640                 (cond ((equal tag "Prev")
2641                        (put-text-property tbeg nend 'keymap
2642                                           Info-prev-link-keymap))
2643                       ((equal tag "Next")
2644                        (put-text-property tbeg nend 'keymap
2645                                           Info-next-link-keymap))
2646                       ((equal tag "Up")
2647                        (put-text-property tbeg nend 'keymap
2648                                           Info-up-link-keymap))))))
2649           (goto-char (point-min))
2650           (let ((header-end (save-excursion (end-of-line) (point)))
2651                 header)
2652             ;; If we find neither Next: nor Prev: link, show the entire
2653             ;; node header.  Otherwise, don't show the File: and Node:
2654             ;; parts, to avoid wasting precious space on information that
2655             ;; is available in the mode line.
2656             (if (re-search-forward
2657                  "\\(next\\|up\\|prev[ious]*\\): "
2658                  header-end t)
2659                 (progn
2660                   (goto-char (match-beginning 1))
2661                   (setq header (buffer-substring (point) header-end)))
2662               (if (re-search-forward "node:[ \t]*[^ \t]+[ \t]*" nil t)
2663                   (setq header
2664                         (concat "No next, prev or up links  --  "
2665                                 (buffer-substring (point) header-end)))
2666                 (setq header (buffer-substring (point) header-end))))
2667
2668             (put-text-property (point-min) (1+ (point-min))
2669                                'header-line header)
2670             ;; Hide the part of the first line
2671             ;; that is in the header, if it is just part.
2672             (unless (bobp)
2673               ;; Hide the punctuation at the end, too.
2674               (skip-chars-backward " \t,")
2675               (put-text-property (point) header-end 'invisible t))))
2676         (goto-char (point-min))
2677         (while (re-search-forward "\n\\([^ \t\n].+\\)\n\\(\\*+\\|=+\\|-+\\|\\.+\\)$"
2678                                   nil t)
2679           (let* ((c (preceding-char))
2680                  (face
2681                   (cond ((= c ?*) 'Info-title-1-face)
2682                         ((= c ?=) 'Info-title-2-face)
2683                         ((= c ?-) 'Info-title-3-face)
2684                         (t        'Info-title-4-face))))
2685             (put-text-property (match-beginning 1) (match-end 1)
2686                                'font-lock-face face))
2687           ;; This is a serious problem for trying to handle multiple
2688           ;; frame types at once.  We want this text to be invisible
2689           ;; on frames that can display the font above.
2690           (when (memq (framep (selected-frame)) '(x pc w32 mac))
2691             (add-text-properties (match-beginning 2) (1+ (match-end 2))
2692                                  '(invisible t intangible t))))
2693         (goto-char (point-min))
2694         (while (re-search-forward "\\*Note[ \n\t]+\\([^:]*\\):" nil t)
2695           (if (= (char-after (1- (match-beginning 0))) ?\") ; hack
2696               nil
2697             (add-text-properties (match-beginning 1) (match-end 1)
2698                                  '(font-lock-face info-xref
2699                                    mouse-face highlight
2700                                    help-echo "mouse-2: go to this node"))))
2701         (goto-char (point-min))
2702         (if (and (search-forward "\n* Menu:" nil t)
2703                  (not (string-match "\\<Index\\>" Info-current-node))
2704                  ;; Don't take time to annotate huge menus
2705                  (< (- (point-max) (point)) Info-fontify-maximum-menu-size))
2706             (let ((n 0))
2707               (while (re-search-forward "^\\* +\\([^:\t\n]*\\):" nil t)
2708                 (setq n (1+ n))
2709                 (if (zerop (% n 3)) ; visual aids to help with 1-9 keys
2710                     (put-text-property (match-beginning 0)
2711                                        (1+ (match-beginning 0))
2712                                        'font-lock-face 'info-menu-5))
2713                 (add-text-properties (match-beginning 1) (match-end 1)
2714                                      '(font-lock-face info-xref
2715                                        mouse-face highlight
2716                                        help-echo "mouse-2: go to this node")))))
2717         (Info-fontify-menu-headers)
2718         (set-buffer-modified-p nil)))))
2719 \f
2720
2721 ;; When an Info buffer is killed, make sure the associated tags buffer
2722 ;; is killed too.
2723 (defun Info-kill-buffer ()
2724   (and (eq major-mode 'Info-mode)
2725        Info-tag-table-buffer
2726        (kill-buffer Info-tag-table-buffer)))
2727
2728 (add-hook 'kill-buffer-hook 'Info-kill-buffer)
2729
2730 ;;; Speedbar support:
2731 ;; These functions permit speedbar to display the "tags" in the
2732 ;; current info node.
2733 (eval-when-compile (require 'speedbar))
2734
2735 (defvar Info-speedbar-key-map nil
2736   "Keymap used when in the info display mode.")
2737
2738 (defun Info-install-speedbar-variables ()
2739   "Install those variables used by speedbar to enhance Info."
2740   (if Info-speedbar-key-map
2741       nil
2742     (setq Info-speedbar-key-map (speedbar-make-specialized-keymap))
2743
2744     ;; Basic tree features
2745     (define-key Info-speedbar-key-map "e" 'speedbar-edit-line)
2746     (define-key Info-speedbar-key-map "\C-m" 'speedbar-edit-line)
2747     (define-key Info-speedbar-key-map "+" 'speedbar-expand-line)
2748     (define-key Info-speedbar-key-map "-" 'speedbar-contract-line)
2749     )
2750
2751   (speedbar-add-expansion-list '("Info" Info-speedbar-menu-items
2752                                  Info-speedbar-key-map
2753                                  Info-speedbar-hierarchy-buttons)))
2754
2755 (defvar Info-speedbar-menu-items
2756   '(["Browse Node" speedbar-edit-line t]
2757     ["Expand Node" speedbar-expand-line
2758      (save-excursion (beginning-of-line)
2759                      (looking-at "[0-9]+: *.\\+. "))]
2760     ["Contract Node" speedbar-contract-line
2761      (save-excursion (beginning-of-line)
2762                      (looking-at "[0-9]+: *.-. "))]
2763     )
2764   "Additional menu-items to add to speedbar frame.")
2765
2766 ;; Make sure our special speedbar major mode is loaded
2767 (if (featurep 'speedbar)
2768     (Info-install-speedbar-variables)
2769   (add-hook 'speedbar-load-hook 'Info-install-speedbar-variables))
2770
2771 ;;; Info hierarchy display method
2772 ;;;###autoload
2773 (defun Info-speedbar-browser ()
2774   "Initialize speedbar to display an info node browser.
2775 This will add a speedbar major display mode."
2776   (interactive)
2777   (require 'speedbar)
2778   ;; Make sure that speedbar is active
2779   (speedbar-frame-mode 1)
2780   ;; Now, throw us into Info mode on speedbar.
2781   (speedbar-change-initial-expansion-list "Info")
2782   )
2783
2784 (eval-when-compile (defvar speedbar-attached-frame))
2785
2786 (defun Info-speedbar-hierarchy-buttons (directory depth &optional node)
2787   "Display an Info directory hierarchy in speedbar.
2788 DIRECTORY is the current directory in the attached frame.
2789 DEPTH is the current indentation depth.
2790 NODE is an optional argument that is used to represent the
2791 specific node to expand."
2792   (if (and (not node)
2793            (save-excursion (goto-char (point-min))
2794                            (let ((case-fold-search t))
2795                              (looking-at "Info Nodes:"))))
2796       ;; Update our "current node" maybe?
2797       nil
2798     ;; We cannot use the generic list code, that depends on all leaves
2799     ;; being known at creation time.
2800     (if (not node)
2801         (speedbar-with-writable (insert "Info Nodes:\n")))
2802     (let ((completions nil)
2803           (cf (selected-frame)))
2804       (select-frame speedbar-attached-frame)
2805       (save-window-excursion
2806         (setq completions
2807               (Info-speedbar-fetch-file-nodes (or node '"(dir)top"))))
2808       (select-frame cf)
2809       (if completions
2810           (speedbar-with-writable
2811            (while completions
2812              (speedbar-make-tag-line 'bracket ?+ 'Info-speedbar-expand-node
2813                                      (cdr (car completions))
2814                                      (car (car completions))
2815                                      'Info-speedbar-goto-node
2816                                      (cdr (car completions))
2817                                      'info-xref depth)
2818              (setq completions (cdr completions)))
2819            t)
2820         nil))))
2821
2822 (defun Info-speedbar-goto-node (text node indent)
2823   "When user clicks on TEXT, go to an info NODE.
2824 The INDENT level is ignored."
2825   (select-frame speedbar-attached-frame)
2826   (let* ((buff (or (get-buffer "*info*")
2827                    (progn (info) (get-buffer "*info*"))))
2828          (bwin (get-buffer-window buff 0)))
2829     (if bwin
2830         (progn
2831           (select-window bwin)
2832           (raise-frame (window-frame bwin)))
2833       (if speedbar-power-click
2834           (let ((pop-up-frames t)) (select-window (display-buffer buff)))
2835         (select-frame speedbar-attached-frame)
2836         (switch-to-buffer buff)))
2837     (let ((junk (string-match "^(\\([^)]+\\))\\([^.]+\\)$" node))
2838           (file (match-string 1 node))
2839           (node (match-string 2 node)))
2840       (Info-find-node file node)
2841       ;; If we do a find-node, and we were in info mode, restore
2842       ;; the old default method.  Once we are in info mode, it makes
2843       ;; sense to return to whatever method the user was using before.
2844       (if (string= speedbar-initial-expansion-list-name "Info")
2845           (speedbar-change-initial-expansion-list
2846            speedbar-previously-used-expansion-list-name)))))
2847
2848 (defun Info-speedbar-expand-node (text token indent)
2849   "Expand the node the user clicked on.
2850 TEXT is the text of the button we clicked on, a + or - item.
2851 TOKEN is data related to this node (NAME . FILE).
2852 INDENT is the current indentation depth."
2853   (cond ((string-match "+" text)        ;we have to expand this file
2854          (speedbar-change-expand-button-char ?-)
2855          (if (speedbar-with-writable
2856               (save-excursion
2857                 (end-of-line) (forward-char 1)
2858                 (Info-speedbar-hierarchy-buttons nil (1+ indent) token)))
2859              (speedbar-change-expand-button-char ?-)
2860            (speedbar-change-expand-button-char ??)))
2861         ((string-match "-" text)        ;we have to contract this node
2862          (speedbar-change-expand-button-char ?+)
2863          (speedbar-delete-subblock indent))
2864         (t (error "Ooops... not sure what to do")))
2865   (speedbar-center-buffer-smartly))
2866
2867 (defun Info-speedbar-fetch-file-nodes (nodespec)
2868   "Fetch the subnodes from the info NODESPEC.
2869 NODESPEC is a string of the form: (file)node.
2870 Optional THISFILE represends the filename of"
2871   (save-excursion
2872     ;; Set up a buffer we can use to fake-out Info.
2873     (set-buffer (get-buffer-create "*info-browse-tmp*"))
2874     (if (not (equal major-mode 'Info-mode))
2875         (Info-mode))
2876     ;; Get the node into this buffer
2877     (let ((junk (string-match "^(\\([^)]+\\))\\([^.]+\\)$" nodespec))
2878           (file (match-string 1 nodespec))
2879           (node (match-string 2 nodespec)))
2880       (Info-find-node file node))
2881     ;; Scan the created buffer
2882     (goto-char (point-min))
2883     (let ((completions nil)
2884           (case-fold-search t)
2885           (thisfile (progn (string-match "^(\\([^)]+\\))" nodespec)
2886                            (match-string 1 nodespec))))
2887       ;; Always skip the first one...
2888       (re-search-forward "\n\\* \\([^:\t\n]*\\):" nil t)
2889       (while (re-search-forward "\n\\* \\([^:\t\n]*\\):" nil t)
2890         (let ((name (match-string 1)))
2891           (if (looking-at " *\\(([^)]+)[^.\n]+\\)\\.")
2892               (setq name (cons name (match-string 1)))
2893             (if (looking-at " *\\(([^)]+)\\)\\.")
2894                 (setq name (cons name (concat (match-string 1) "Top")))
2895               (if (looking-at " \\([^.]+\\).")
2896                   (setq name
2897                         (cons name (concat "(" thisfile ")" (match-string 1))))
2898                 (setq name (cons name (concat "(" thisfile ")" name))))))
2899           (setq completions (cons name completions))))
2900       (nreverse completions))))
2901
2902 ;;; Info mode node listing
2903 (defun Info-speedbar-buttons (buffer)
2904   "Create a speedbar display to help navigation in an Info file.
2905 BUFFER is the buffer speedbar is requesting buttons for."
2906   (if (save-excursion (goto-char (point-min))
2907                       (let ((case-fold-search t))
2908                         (not (looking-at "Info Nodes:"))))
2909       (erase-buffer))
2910   (Info-speedbar-hierarchy-buttons nil 0)
2911   )
2912
2913 (dolist (mess '("^Node has no Previous$"
2914                 "^No menu in this node$"
2915                 "^Node has no Next$"
2916                 "^No cross-references in this node^"
2917                 search-failed
2918                 "^No \".*\" in index$"))
2919   (add-to-list 'debug-ignored-errors mess))
2920
2921 (provide 'info)
2922
2923 ;;; info.el ends here