info.el 170 KB
Newer Older
1
;;; info.el --- info package for Emacs
Eric S. Raymond's avatar
Eric S. Raymond committed
2

3
;; Copyright (C) 1985, 1986, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4 5
;;   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
;;   Free Software Foundation, Inc.
Eric S. Raymond's avatar
Eric S. Raymond committed
6

Eric S. Raymond's avatar
Eric S. Raymond committed
7
;; Maintainer: FSF
Eric S. Raymond's avatar
Eric S. Raymond committed
8
;; Keywords: help
Eric S. Raymond's avatar
Eric S. Raymond committed
9

Jim Blandy's avatar
Jim Blandy committed
10 11
;; This file is part of GNU Emacs.

12
;; GNU Emacs is free software: you can redistribute it and/or modify
Jim Blandy's avatar
Jim Blandy committed
13
;; it under the terms of the GNU General Public License as published by
14 15
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
Jim Blandy's avatar
Jim Blandy committed
16 17 18 19 20 21 22

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

;; You should have received a copy of the GNU General Public License
23
;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
Jim Blandy's avatar
Jim Blandy committed
24

Eric S. Raymond's avatar
Eric S. Raymond committed
25 26
;;; Commentary:

27
;; Note that nowadays we expect Info files to be made using makeinfo.
28 29 30 31
;; In particular we make these assumptions:
;;  - a menu item MAY contain colons but not colon-space ": "
;;  - a menu item ending with ": " (but not ":: ") is an index entry
;;  - a node name MAY NOT contain a colon
32 33
;; This distinction is to support indexing of computer programming
;; language terms that may contain ":" but not ": ".
Eric S. Raymond's avatar
Eric S. Raymond committed
34 35 36

;;; Code:

37
(eval-when-compile (require 'jka-compr) (require 'cl))
Dave Love's avatar
Dave Love committed
38

39
(defgroup info nil
40
  "Info subsystem."
41 42 43 44
  :group 'help
  :group 'docs)


Jim Blandy's avatar
Jim Blandy committed
45
(defvar Info-history nil
46
  "Stack of Info nodes user has visited.
47
Each element of the stack is a list (FILENAME NODENAME BUFFERPOS).")
Jim Blandy's avatar
Jim Blandy committed
48

49
(defvar Info-history-forward nil
50
  "Stack of Info nodes user has visited with `Info-history-back' command.
51
Each element of the stack is a list (FILENAME NODENAME BUFFERPOS).")
52

Juri Linkov's avatar
Juri Linkov committed
53
(defvar Info-history-list nil
54
  "List of all Info nodes user has visited.
55
Each element of the list is a list (FILENAME NODENAME).")
Juri Linkov's avatar
Juri Linkov committed
56

57
(defcustom Info-enable-edit nil
58
  "*Non-nil means the \\<Info-mode-map>\\[Info-edit] command in Info can edit the current node.
59
This is convenient if you want to write Info files by hand.
60 61
However, we recommend that you not do this.
It is better to write a Texinfo file and generate the Info file from that,
62 63 64
because that gives you a printed manual as well."
  :type 'boolean
  :group 'info)
Jim Blandy's avatar
Jim Blandy committed
65

66
(defvar Info-enable-active-nodes nil
Jim Blandy's avatar
Jim Blandy committed
67 68
  "Non-nil allows Info to execute Lisp code associated with nodes.
The Lisp code is executed when the node is selected.")
69
(put 'Info-enable-active-nodes 'risky-local-variable t)
Jim Blandy's avatar
Jim Blandy committed
70

71
(defface info-node
72 73 74
  '((((class color) (background light)) :foreground "brown" :weight bold :slant italic)
    (((class color) (background dark)) :foreground "white" :weight bold :slant italic)
    (t :weight bold :slant italic))
75 76 77
  "Face for Info node names."
  :group 'info)

78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123
(defface info-title-1
  '((((type tty pc) (class color) (background light))
     :foreground "green" :weight bold)
    (((type tty pc) (class color) (background dark))
     :foreground "yellow" :weight bold)
    (t :height 1.2 :inherit info-title-2))
  "Face for info titles at level 1."
  :group 'info)
;; backward-compatibility alias
(put 'Info-title-1-face 'face-alias 'info-title-1)

(defface info-title-2
  '((((type tty pc) (class color)) :foreground "lightblue" :weight bold)
    (t :height 1.2 :inherit info-title-3))
  "Face for info titles at level 2."
  :group 'info)
;; backward-compatibility alias
(put 'Info-title-2-face 'face-alias 'info-title-2)

(defface info-title-3
  '((((type tty pc) (class color)) :weight bold)
    (t :height 1.2 :inherit info-title-4))
  "Face for info titles at level 3."
  :group 'info)
;; backward-compatibility alias
(put 'Info-title-3-face 'face-alias 'info-title-3)

(defface info-title-4
  '((((type tty pc) (class color)) :weight bold)
    (t :weight bold :inherit variable-pitch))
  "Face for info titles at level 4."
  :group 'info)
;; backward-compatibility alias
(put 'Info-title-4-face 'face-alias 'info-title-4)

(defface info-menu-header
  '((((type tty pc))
     :underline t
     :weight bold)
    (t
     :inherit variable-pitch
     :weight bold))
  "Face for headers in Info menus."
  :group 'info)

(defface info-menu-star
124 125
  '((((class color)) :foreground "red1")
    (t :underline t))
126
  "Face for every third `*' in an Info menu."
127
  :group 'info)
128
(put 'info-menu-5 'face-alias 'info-menu-star)
129 130

(defface info-xref
131 132
  '((t :inherit link))
  "Face for unvisited Info cross-references."
133 134
  :group 'info)

Juri Linkov's avatar
Juri Linkov committed
135
(defface info-xref-visited
136
  '((t :inherit (link-visited info-xref)))
Juri Linkov's avatar
Juri Linkov committed
137
  "Face for visited Info cross-references."
138
  :version "22.1"
Juri Linkov's avatar
Juri Linkov committed
139 140 141
  :group 'info)

(defcustom Info-fontify-visited-nodes t
142
  "*Non-nil to fontify references to visited nodes in `info-xref-visited' face."
143
  :version "22.1"
Juri Linkov's avatar
Juri Linkov committed
144 145 146
  :type 'boolean
  :group 'info)

147
(defcustom Info-fontify-maximum-menu-size 100000
148 149
  "*Maximum size of menu to fontify if `font-lock-mode' is non-nil.
Set to nil to disable node fontification."
150 151
  :type 'integer
  :group 'info)
152

Miles Bader's avatar
Miles Bader committed
153
(defcustom Info-use-header-line t
154
  "*Non-nil means to put the beginning-of-node links in an Emacs header-line.
Miles Bader's avatar
Miles Bader committed
155 156 157 158 159
A header-line does not scroll with the rest of the buffer."
  :type 'boolean
  :group 'info)

(defface info-header-xref
160
  '((t :inherit info-xref))
Miles Bader's avatar
Miles Bader committed
161 162 163 164
  "Face for Info cross-references in a node header."
  :group 'info)

(defface info-header-node
165
  '((t :inherit info-node))
Miles Bader's avatar
Miles Bader committed
166 167 168
  "Face for Info nodes in a node header."
  :group 'info)

169
(defvar Info-directory-list nil
Jim Blandy's avatar
Jim Blandy committed
170
  "List of directories to search for Info documentation files.
171
If nil, meaning not yet initialized, Info uses the environment
172
variable INFOPATH to initialize it, or `Info-default-directory-list'
173 174
if there is no INFOPATH variable in the environment, or the
concatenation of the two if INFOPATH ends with a colon.
175 176

When `Info-directory-list' is initialized from the value of
177 178 179 180 181 182 183
`Info-default-directory-list', and Emacs is installed in one of the
standard directories, the directory of Info files that come with Emacs
is put last (so that local Info files override standard ones).

When `Info-directory-list' is initialized from the value of
`Info-default-directory-list', and Emacs is not installed in one
of the standard directories, the first element of the resulting
184 185
list is the directory where Emacs installs the Info files that
come with it.  This is so that Emacs's own manual, which suits the
186 187 188 189 190 191
version of Emacs you are using, will always be found first.  This
is useful when you install an experimental version of Emacs without
removing the standard installation.

If you want to override the order of directories in
`Info-default-directory-list', set INFOPATH in the environment.
192 193

If you run the Emacs executable from the `src' directory in the Emacs
194 195 196 197
source tree, and INFOPATH is not defined, the `info' directory in the
source tree is used as the first element of `Info-directory-list', in
place of the installation Info directory.  This is useful when you run
a version of Emacs without installing it.")
Jim Blandy's avatar
Jim Blandy committed
198

199
(defcustom Info-additional-directory-list nil
200
  "List of additional directories to search for Info documentation files.
201
These directories are searched after those in `Info-directory-list'."
202 203
  :type '(repeat directory)
  :group 'info)
204

205
(defcustom Info-scroll-prefer-subnodes nil
206
  "*If non-nil, \\<Info-mode-map>\\[Info-scroll-up] in a menu visits subnodes.
207

208 209 210 211 212 213 214 215
If this is non-nil, and you scroll far enough in a node that its menu
appears on the screen, the next \\<Info-mode-map>\\[Info-scroll-up]
moves to a subnode indicated by the following menu item.  This means
that you visit a subnode before getting to the end of the menu.

Setting this option to nil results in behavior similar to the stand-alone
Info reader program, which visits the first subnode from the menu only
when you hit the end of the current node."
216
  :version "22.1"
217 218 219
  :type 'boolean
  :group 'info)

220
(defcustom Info-hide-note-references t
221
  "*If non-nil, hide the tag and section reference in *note and * menu items.
Juri Linkov's avatar
Juri Linkov committed
222
If value is non-nil but not `hide', also replaces the \"*note\" with \"see\".
223
If value is non-nil but not t or `hide', the reference section is still shown.
224 225
`nil' completely disables this feature.  If this is non-nil, you might
want to set `Info-refill-paragraphs'."
226
  :version "22.1"
Juri Linkov's avatar
Juri Linkov committed
227
  :type '(choice (const :tag "No hiding" nil)
228
		 (const :tag "Replace tag and hide reference" t)
Juri Linkov's avatar
Juri Linkov committed
229 230
		 (const :tag "Hide tag and reference" hide)
		 (other :tag "Only replace tag" tag))
231 232
  :group 'info)

Kim F. Storm's avatar
Kim F. Storm committed
233 234
(defcustom Info-refill-paragraphs nil
  "*If non-nil, attempt to refill paragraphs with hidden references.
235
This refilling may accidentally remove explicit line breaks in the Info
236 237
file, so be prepared for a few surprises if you enable this feature.
This only has an effect if `Info-hide-note-references' is non-nil."
238
  :version "22.1"
Kim F. Storm's avatar
Kim F. Storm committed
239 240 241
  :type 'boolean
  :group 'info)

242
(defcustom Info-search-whitespace-regexp "\\s-+"
Juri Linkov's avatar
Juri Linkov committed
243 244 245 246 247 248 249 250
  "*If non-nil, regular expression to match a sequence of whitespace chars.
This applies to Info search for regular expressions.
You might want to use something like \"[ \\t\\r\\n]+\" instead.
In the Customization buffer, that is `[' followed by a space,
a tab, a carriage return (control-M), a newline, and `]+'."
  :type 'regexp
  :group 'info)

251
(defcustom Info-isearch-search t
252 253 254 255 256 257 258 259 260 261 262
  "*If non-nil, isearch in Info searches through multiple nodes.
Before leaving the initial Info node, where isearch was started,
it fails once with the error message [initial node], and with
subsequent C-s/C-r continues through other nodes without failing
with this error message in other nodes.  When isearch fails for
the rest of the manual, it wraps aroung the whole manual and
restarts the search from the top/final node depending on
search direction.

Setting this option to nil restores the default isearch behavior
with wrapping around the current Info node."
263 264 265 266
  :version "22.1"
  :type 'boolean
  :group 'info)

267 268
(defvar Info-isearch-initial-node nil)

269 270 271 272
(defcustom Info-mode-hook
  ;; Try to obey obsolete Info-fontify settings.
  (unless (and (boundp 'Info-fontify) (null Info-fontify))
    '(turn-on-font-lock))
Juri Linkov's avatar
Juri Linkov committed
273 274 275 276 277 278
  "Hooks run when `Info-mode' is called."
  :type 'hook
  :group 'info)

(defcustom Info-selection-hook nil
  "Hooks run when `Info-select-node' is called."
Colin Walters's avatar
Colin Walters committed
279 280 281
  :type 'hook
  :group 'info)

Juri Linkov's avatar
Juri Linkov committed
282 283 284
(defvar Info-edit-mode-hook nil
  "Hooks run when `Info-edit-mode' is called.")

Jim Blandy's avatar
Jim Blandy committed
285
(defvar Info-current-file nil
286 287
  "Info file that Info is now looking at, or nil.
This is the name that was specified in Info, not the actual file name.
288
It doesn't contain directory names or file name extensions added by Info.")
Jim Blandy's avatar
Jim Blandy committed
289 290

(defvar Info-current-subfile nil
Dave Love's avatar
Dave Love committed
291
  "Info subfile that is actually in the *info* buffer now.
292
It is nil if current Info file is not split into subfiles.")
Jim Blandy's avatar
Jim Blandy committed
293 294 295 296

(defvar Info-current-node nil
  "Name of node that Info is now looking at, or nil.")

297
(defvar Info-tag-table-marker nil
Jim Blandy's avatar
Jim Blandy committed
298 299 300
  "Marker pointing at beginning of current Info file's tag table.
Marker points nowhere if file has no tag table.")

301 302 303
(defvar Info-tag-table-buffer nil
  "Buffer used for indirect tag tables.")

304 305 306
(defvar Info-current-file-completions nil
  "Cached completion list for current Info file.")

307 308 309
(defvar Info-file-supports-index-cookies nil
  "Non-nil if current Info file supports index cookies.")

310
(defvar Info-index-alternatives nil
Dave Love's avatar
Dave Love committed
311
  "List of possible matches for last `Info-index' command.")
312

313 314 315 316 317
(defvar Info-point-loc nil
  "Point location within a selected node.
If string, the point is moved to the proper occurrence of the
name of the followed cross reference within a selected node.
If number, the point is moved to the corresponding line.")
Juri Linkov's avatar
Juri Linkov committed
318

319 320
(defvar Info-standalone nil
  "Non-nil if Emacs was started solely as an Info browser.")
321

322
(defvar Info-suffix-list
323 324
  ;; The MS-DOS list should work both when long file names are
  ;; supported (Windows 9X), and when only 8+3 file names are available.
325 326 327
  (if (eq system-type 'ms-dos)
      '( (".gz"      . "gunzip")
	 (".z"       . "gunzip")
328
	 (".bz2"     . ("bzip2" "-dc"))
329 330 331 332 333 334 335 336
	 (".inz"     . "gunzip")
	 (".igz"     . "gunzip")
	 (".info.Z"  . "gunzip")
	 (".info.gz" . "gunzip")
	 ("-info.Z"  . "gunzip")
	 ("-info.gz" . "gunzip")
	 ("/index.gz". "gunzip")
	 ("/index.z" . "gunzip")
337
	 (".inf"     . nil)
338 339 340
	 (".info"    . nil)
	 ("-info"    . nil)
	 ("/index"   . nil)
341
	 (""         . nil))
342 343 344 345
    '( (".info.Z".    "uncompress")
       (".info.Y".    "unyabba")
       (".info.gz".   "gunzip")
       (".info.z".    "gunzip")
346
       (".info.bz2" . ("bzip2" "-dc"))
347 348 349 350
       (".info".      nil)
       ("-info.Z".   "uncompress")
       ("-info.Y".   "unyabba")
       ("-info.gz".  "gunzip")
351
       ("-info.bz2" . ("bzip2" "-dc"))
352 353 354 355 356 357
       ("-info.z".   "gunzip")
       ("-info".     nil)
       ("/index.Z".   "uncompress")
       ("/index.Y".   "unyabba")
       ("/index.gz".  "gunzip")
       ("/index.z".   "gunzip")
358
       ("/index.bz2". ("bzip2" "-dc"))
359 360 361 362 363
       ("/index".     nil)
       (".Z".         "uncompress")
       (".Y".         "unyabba")
       (".gz".        "gunzip")
       (".z".         "gunzip")
364
       (".bz2" .      ("bzip2" "-dc"))
365
       ("".           nil)))
366 367
  "List of file name suffixes and associated decoding commands.
Each entry should be (SUFFIX . STRING); the file is given to
368 369 370 371 372 373
the command as standard input.

STRING may be a list of strings.  In that case, the first element is
the command name, and the rest are arguments to that command.

If STRING is nil, no decoding is done.
374 375
Because the SUFFIXes are tried in order, the empty string should
be last in the list.")
376

377
;; Concatenate SUFFIX onto FILENAME.  SUFFIX should start with a dot.
378 379 380 381
;; First, on MS-DOS with no long file names support, delete some of
;; the extension in FILENAME to make room.
(defun info-insert-file-contents-1 (filename suffix lfn)
  (if lfn	; long file names are supported
382 383
      (concat filename suffix)
    (let* ((sans-exts (file-name-sans-extension filename))
384 385 386
	   ;; How long is the extension in FILENAME (not counting the dot).
	   (ext-len (max 0 (- (length filename) (length sans-exts) 1)))
	   ext-left)
387
      ;; SUFFIX starts with a dot.  If FILENAME already has one,
388
      ;; get rid of the one in SUFFIX (unless suffix is empty).
389
      (or (and (<= ext-len 0)
390
	       (not (eq (aref filename (1- (length filename))) ?.)))
391
	  (= (length suffix) 0)
392
	  (setq suffix (substring suffix 1)))
393 394
      ;; How many chars of that extension should we keep?
      (setq ext-left (min ext-len (max 0 (- 3 (length suffix)))))
395 396 397 398 399
      ;; Get rid of the rest of the extension, and add SUFFIX.
      (concat (substring filename 0 (- (length filename)
				       (- ext-len ext-left)))
	      suffix))))

400 401 402 403
(defun info-file-exists-p (filename)
  (and (file-exists-p filename)
       (not (file-directory-p filename))))

404
(defun info-insert-file-contents (filename &optional visit)
405
  "Insert the contents of an Info file in the current buffer.
406
Do the right thing if the file has been compressed or zipped."
407
  (let* ((tail Info-suffix-list)
408 409 410
	 (lfn (if (fboundp 'msdos-long-file-names)
		  (msdos-long-file-names)
		t))
411 412 413
	 (check-short (and (fboundp 'msdos-long-file-names)
			   lfn))
	 fullname decoder done)
414
    (if (info-file-exists-p filename)
415 416
	;; FILENAME exists--see if that name contains a suffix.
	;; If so, set DECODE accordingly.
417 418 419 420 421 422 423 424
	(progn
	  (while (and tail
		      (not (string-match
			    (concat (regexp-quote (car (car tail))) "$")
			    filename)))
	    (setq tail (cdr tail)))
	  (setq fullname filename
		decoder (cdr (car tail))))
425
      ;; Try adding suffixes to FILENAME and see if we can find something.
426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441
      (while (and tail (not done))
	(setq fullname (info-insert-file-contents-1 filename
						    (car (car tail)) lfn))
	(if (info-file-exists-p fullname)
	    (setq done t
		  ;; If we found a file with a suffix, set DECODER
		  ;; according to the suffix.
		  decoder (cdr (car tail)))
	  ;; When the MS-DOS port runs on Windows, we need to check
	  ;; the short variant of a long file name as well.
	  (when check-short
	    (setq fullname (info-insert-file-contents-1 filename
							(car (car tail)) nil))
	    (if (info-file-exists-p fullname)
		(setq done t
		      decoder (cdr (car tail))))))
442 443
	(setq tail (cdr tail)))
      (or tail
444
	  (error "Can't find %s or any compressed version of it" filename)))
445
    ;; check for conflict with jka-compr
446
    (if (and (jka-compr-installed-p)
447 448
	     (jka-compr-get-compression-info fullname))
	(setq decoder nil))
449
    (if decoder
450 451
	(progn
	  (insert-file-contents-literally fullname visit)
452
	  (let ((inhibit-read-only t)
453 454 455
		(coding-system-for-write 'no-conversion)
		(default-directory (or (file-name-directory fullname)
				       default-directory)))
456 457 458 459
	    (or (consp decoder)
		(setq decoder (list decoder)))
	    (apply 'call-process-region (point-min) (point-max)
		   (car decoder) t t nil (cdr decoder))))
460
      (insert-file-contents fullname visit))))
461

462 463 464 465 466 467
(defun Info-default-dirs ()
  (let ((source (expand-file-name "info/" source-directory))
	(sibling (if installation-directory
		     (expand-file-name "info/" installation-directory)
		   (if invocation-directory
		       (let ((infodir (expand-file-name
468
				       "../share/info/"
469 470 471 472
				       invocation-directory)))
			 (if (file-exists-p infodir)
			     infodir
			   (setq infodir (expand-file-name
473
					  "../../../share/info/"
474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499
					  invocation-directory))
			   (and (file-exists-p infodir)
				infodir))))))
	alternative)
    (setq alternative
	  (if (and sibling (file-exists-p sibling))
	      ;; Uninstalled, Emacs builddir != srcdir.
	      sibling
	    ;; Uninstalled, builddir == srcdir
	    source))
    (if (or (member alternative Info-default-directory-list)
	    ;; On DOS/NT, we use movable executables always,
	    ;; and we must always find the Info dir at run time.
	    (if (memq system-type '(ms-dos windows-nt))
		nil
	      ;; Use invocation-directory for Info
	      ;; only if we used it for exec-directory also.
	      (not (string= exec-directory
			    (expand-file-name "lib-src/"
					      installation-directory))))
	    (not (file-exists-p alternative)))
	Info-default-directory-list
      ;; `alternative' contains the Info files that came with this
      ;; version, so we should look there first.  `Info-insert-dir'
      ;; currently expects to find `alternative' first on the list.
      (cons alternative
500 501 502
	    ;; Don't drop the last part, it might contain non-Emacs stuff.
	    ;; (reverse (cdr (reverse
	    Info-default-directory-list)))) ;; )))
503

504
(defun info-initialize ()
Dave Love's avatar
Dave Love committed
505
  "Initialize `Info-directory-list', if that hasn't been done yet."
506
  (unless Info-directory-list
507
    (let ((path (getenv "INFOPATH")))
508
      (setq Info-directory-list
509 510
	    (prune-directory-list
	     (if path
511 512 513 514 515 516
		 (if (string-match ":\\'" path)
		     (append (split-string (substring path 0 -1)
					   (regexp-quote path-separator))
			     (Info-default-dirs))
		   (split-string path (regexp-quote path-separator)))
	       (Info-default-dirs)))))))
517

518
;;;###autoload
519
(defun info-other-window (&optional file-or-node)
520 521 522
  "Like `info' but show the Info buffer in another window."
  (interactive (if current-prefix-arg
		   (list (read-file-name "Info file name: " nil nil t))))
523
  (let (same-window-buffer-names same-window-regexps)
524
    (info file-or-node)))
525

526
;;;###autoload (add-hook 'same-window-regexps "\\*info\\*\\(\\|<[0-9]+>\\)")
527

528
;;;###autoload (put 'info 'info-file "emacs")
Jim Blandy's avatar
Jim Blandy committed
529
;;;###autoload
530
(defun info (&optional file-or-node buffer)
Jim Blandy's avatar
Jim Blandy committed
531
  "Enter Info, the documentation browser.
532
Optional argument FILE-OR-NODE specifies the file to examine;
Jim Blandy's avatar
Jim Blandy committed
533
the default is the top-level directory of Info.
534
Called from a program, FILE-OR-NODE may specify an Info node of the form
Dave Love's avatar
Dave Love committed
535
`(FILENAME)NODENAME'.
536 537 538 539
Optional argument BUFFER specifies the Info buffer name;
the default buffer name is *info*.  If BUFFER exists,
just switch to BUFFER.  Otherwise, create a new buffer
with the top-level Info directory.
Jim Blandy's avatar
Jim Blandy committed
540

541 542
In interactive use, a non-numeric prefix argument directs
this command to read a file name from the minibuffer.
Juri Linkov's avatar
Juri Linkov committed
543 544
A numeric prefix argument selects an Info buffer with the prefix number
appended to the Info buffer name.
Richard M. Stallman's avatar
Richard M. Stallman committed
545 546

The search path for Info files is in the variable `Info-directory-list'.
547
The top-level Info directory is made by combining all the files named `dir'
Juri Linkov's avatar
Juri Linkov committed
548 549 550
in all the directories in that path.

See a list of available Info commands in `Info-mode'."
551 552 553 554 555 556 557 558
  (interactive (list
                (if (and current-prefix-arg (not (numberp current-prefix-arg)))
                    (read-file-name "Info file name: " nil nil t))
                (if (numberp current-prefix-arg)
                    (format "*info*<%s>" current-prefix-arg))))
  (pop-to-buffer (or buffer "*info*"))
  (if (and buffer (not (eq major-mode 'Info-mode)))
      (Info-mode))
559
  (if file-or-node
560 561 562 563
      ;; If argument already contains parentheses, don't add another set
      ;; since the argument will then be parsed improperly.  This also
      ;; has the added benefit of allowing node names to be included
      ;; following the parenthesized filename.
564
      (Info-goto-node
565 566 567
       (if (and (stringp file-or-node) (string-match "(.*)" file-or-node))
           file-or-node
         (concat "(" file-or-node ")")))
568 569 570 571
    (if (and (zerop (buffer-size))
	     (null Info-history))
	;; If we just created the Info buffer, go to the directory.
	(Info-directory))))
Jim Blandy's avatar
Jim Blandy committed
572

573 574
;;;###autoload
(defun info-emacs-manual ()
575
  "Display the Emacs manual in Info mode."
576 577 578
  (interactive)
  (info "emacs"))

579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595
;;;###autoload
(defun info-standalone ()
  "Run Emacs as a standalone Info reader.
Usage:  emacs -f info-standalone [filename]
In standalone mode, \\<Info-mode-map>\\[Info-exit] exits Emacs itself."
  (setq Info-standalone t)
  (if (and command-line-args-left
	   (not (string-match "^-" (car command-line-args-left))))
      (condition-case err
	  (progn
	    (info (car command-line-args-left))
	    (setq command-line-args-left (cdr command-line-args-left)))
	(error (send-string-to-terminal
		(format "%s\n" (if (eq (car-safe err) 'error)
				   (nth 1 err) err)))
	       (save-buffers-kill-emacs)))
    (info)))
596

Stefan Monnier's avatar
Stefan Monnier committed
597
;; See if the accessible portion of the buffer begins with a node
598 599 600 601 602 603 604 605 606
;; delimiter, and the node header line which follows matches REGEXP.
;; Typically, this test will be followed by a loop that examines the
;; rest of the buffer with (search-forward "\n\^_"), and it's a pity
;; to have the overhead of this special test inside the loop.

;; This function changes match-data, but supposedly the caller might
;; want to use the results of re-search-backward.

;; The return value is the value of point at the beginning of matching
Stefan Monnier's avatar
Stefan Monnier committed
607
;; REGEXP, if the function succeeds, nil otherwise.
608
(defun Info-node-at-bob-matching (regexp)
609 610
  (and (bobp)				; are we at beginning of buffer?
       (looking-at "\^_")		; does it begin with node delimiter?
611 612 613
       (let (beg)
	 (forward-line 1)
	 (setq beg (point))
614
	 (forward-line 1)		; does the line after delimiter match REGEXP?
615 616
	 (re-search-backward regexp beg t))))

Juri Linkov's avatar
Juri Linkov committed
617 618 619 620
(defun Info-find-file (filename &optional noerror)
  "Return expanded FILENAME, or t, if FILENAME is \"dir\".
Optional second argument NOERROR, if t, means if file is not found
just return nil (no error)."
Jim Blandy's avatar
Jim Blandy committed
621 622
  ;; Convert filename to lower case if not found as specified.
  ;; Expand it.
623
  (if (stringp filename)
Jim Blandy's avatar
Jim Blandy committed
624
      (let (temp temp-downcase found)
625
        (setq filename (substitute-in-file-name filename))
Juri Linkov's avatar
Juri Linkov committed
626
	(cond
Jesper Harder's avatar
Jesper Harder committed
627 628 629 630
	 ((string= (downcase filename) "dir")
	  (setq found t))
	 (t
	  (let ((dirs (if (string-match "^\\./" filename)
631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647
                          ;; If specified name starts with `./'
                          ;; then just try current directory.
                          '("./")
                        (if (file-name-absolute-p filename)
                            ;; No point in searching for an
                            ;; absolute file name
                            '(nil)
                          (if Info-additional-directory-list
                              (append Info-directory-list
                                      Info-additional-directory-list)
                            Info-directory-list)))))
            ;; Search the directory list for file FILENAME.
            (while (and dirs (not found))
              (setq temp (expand-file-name filename (car dirs)))
              (setq temp-downcase
                    (expand-file-name (downcase filename) (car dirs)))
              ;; Try several variants of specified name.
648
              (let ((suffix-list Info-suffix-list)
649 650 651
		    (lfn (if (fboundp 'msdos-long-file-names)
			     (msdos-long-file-names)
			   t)))
652 653 654
                (while (and suffix-list (not found))
                  (cond ((info-file-exists-p
                          (info-insert-file-contents-1
655
                           temp (car (car suffix-list)) lfn))
656 657 658
                         (setq found temp))
                        ((info-file-exists-p
                          (info-insert-file-contents-1
659 660 661 662 663 664 665 666
                           temp-downcase (car (car suffix-list)) lfn))
                         (setq found temp-downcase))
			((and (fboundp 'msdos-long-file-names)
			      lfn
			      (info-file-exists-p
			       (info-insert-file-contents-1
				temp (car (car suffix-list)) nil)))
			 (setq found temp)))
667
                  (setq suffix-list (cdr suffix-list))))
Jesper Harder's avatar
Jesper Harder committed
668
              (setq dirs (cdr dirs))))))
669 670
        (if found
            (setq filename found)
Juri Linkov's avatar
Juri Linkov committed
671 672 673
          (if noerror
              (setq filename nil)
            (error "Info file %s does not exist" filename)))
674 675
        filename)
    (and (member filename '(apropos history toc)) filename)))
Juri Linkov's avatar
Juri Linkov committed
676 677

(defun Info-find-node (filename nodename &optional no-going-back)
678
  "Go to an Info node specified as separate FILENAME and NODENAME.
Juri Linkov's avatar
Juri Linkov committed
679 680 681 682
NO-GOING-BACK is non-nil if recovering from an error in this function;
it says do not attempt further (recursive) error recovery."
  (info-initialize)
  (setq filename (Info-find-file filename))
683
  ;; Go into Info buffer.
684
  (or (eq major-mode 'Info-mode) (pop-to-buffer "*info*"))
685 686 687
  ;; Record the node we are leaving, if we were in one.
  (and (not no-going-back)
       Info-current-file
688 689
       (push (list Info-current-file Info-current-node (point))
             Info-history))
690 691
  (Info-find-node-2 filename nodename no-going-back))

692
;;;###autoload
693
(defun Info-on-current-buffer (&optional nodename)
694 695 696
  "Use Info mode to browse the current Info buffer.
With a prefix arg, this queries for the node name to visit first;
otherwise, that defaults to `Top'."
697 698 699
  (interactive
   (list (if current-prefix-arg
	     (completing-read "Node name: " (Info-build-node-completions)
700 701
			      nil t "Top"))))
  (unless nodename (setq nodename "Top"))
702
  (info-initialize)
703
  (Info-mode)
704 705 706 707
  (set (make-local-variable 'Info-current-file)
       (or buffer-file-name
	   ;; If called on a non-file buffer, make a fake file name.
	   (concat default-directory (buffer-name))))
708 709
  (Info-find-node-2 nil nodename))

710
;; It's perhaps a bit nasty to kill the *info* buffer to force a re-read,
711 712
;; but at least it keeps this routine (which is for makeinfo-buffer and
;; Info-revert-buffer-function) out of the way of normal operations.
713 714
;;
(defun Info-revert-find-node (filename nodename)
715
  "Go to an Info node FILENAME and NODENAME, re-reading disk contents.
716 717 718 719 720 721 722 723 724
When *info* is already displaying FILENAME and NODENAME, the window position
is preserved, if possible."
  (pop-to-buffer "*info*")
  (let ((old-filename Info-current-file)
	(old-nodename Info-current-node)
	(pcolumn      (current-column))
	(pline        (count-lines (point-min) (line-beginning-position)))
	(wline        (count-lines (point-min) (window-start)))
	(old-history  Info-history)
725 726
	(new-history  (and Info-current-file
			   (list Info-current-file Info-current-node (point)))))
727 728 729 730 731 732 733
    (kill-buffer (current-buffer))
    (Info-find-node filename nodename)
    (setq Info-history old-history)
    (if (and (equal old-filename Info-current-file)
	     (equal old-nodename Info-current-node))
	(progn
	  ;; note goto-line is no good, we want to measure from point-min
734
	  (goto-char (point-min))
735 736
	  (forward-line wline)
	  (set-window-start (selected-window) (point))
737
	  (goto-char (point-min))
738 739 740 741 742 743
	  (forward-line pline)
	  (move-to-column pcolumn))
      ;; only add to the history when coming from a different file+node
      (if new-history
	  (setq Info-history (cons new-history Info-history))))))

744 745 746 747 748
(defun Info-revert-buffer-function (ignore-auto noconfirm)
  (when (or noconfirm (y-or-n-p "Revert info buffer? "))
    (Info-revert-find-node Info-current-file Info-current-node)
    (message "Reverted %s" Info-current-file)))

749 750 751 752 753 754 755 756 757 758
(defun Info-find-in-tag-table-1 (marker regexp case-fold)
  "Find a node in a tag table.
MARKER specifies the buffer and position to start searching at.
REGEXP is a regular expression matching nodes or references.  Its first
group should match `Node:' or `Ref:'.
CASE-FOLD t means search for a case-insensitive match.
If a match was found, value is a list (FOUND-ANCHOR POS MODE), where
FOUND-ANCHOR is non-nil if a `Ref:' was matched, POS is the position
where the match was found, and MODE is `major-mode' of the buffer in
which the match was found."
759
  (let ((case-fold-search case-fold))
760
    (with-current-buffer (marker-buffer marker)
761
      (goto-char marker)
762

763 764 765 766
      ;; Search tag table
      (beginning-of-line)
      (when (re-search-forward regexp nil t)
	(list (string-equal "Ref:" (match-string 1))
767
	      (+ (point-min) (read (current-buffer)))
768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805
	      major-mode)))))

(defun Info-find-in-tag-table (marker regexp)
  "Find a node in a tag table.
MARKER specifies the buffer and position to start searching at.
REGEXP is a regular expression matching nodes or references.  Its first
group should match `Node:' or `Ref:'.
If a match was found, value is a list (FOUND-ANCHOR POS MODE), where
FOUND-ANCHOR is non-nil if a `Ref:' was matched, POS is the position
where the match was found, and MODE is `major-mode' of the buffer in
which the match was found.
This function tries to find a case-sensitive match first, then a
case-insensitive match is tried."
  (let ((result (Info-find-in-tag-table-1 marker regexp nil)))
    (when (null (car result))
      (setq result (Info-find-in-tag-table-1 marker regexp t)))
    result))

(defun Info-find-node-in-buffer-1 (regexp case-fold)
  "Find a node or anchor in the current buffer.
REGEXP is a regular expression matching nodes or references.  Its first
group should match `Node:' or `Ref:'.
CASE-FOLD t means search for a case-insensitive match.
Value is the position at which a match was found, or nil if not found."
  (let ((case-fold-search case-fold)
	found)
    (save-excursion
      (when (Info-node-at-bob-matching regexp)
	(setq found (point)))
      (while (and (not found)
		  (search-forward "\n\^_" nil t))
	(forward-line 1)
	(let ((beg (point)))
	  (forward-line 1)
	  (when (re-search-backward regexp beg t)
	    (beginning-of-line)
	    (setq found (point)))))
      found)))
806

807 808 809 810 811 812 813 814 815
(defun Info-find-node-in-buffer (regexp)
  "Find a node or anchor in the current buffer.
REGEXP is a regular expression matching nodes or references.  Its first
group should match `Node:' or `Ref:'.
Value is the position at which a match was found, or nil if not found.
This function looks for a case-sensitive match first.  If none is found,
a case-insensitive match is tried."
  (or (Info-find-node-in-buffer-1 regexp nil)
      (Info-find-node-in-buffer-1 regexp t)))
816

817
(defun Info-find-node-2 (filename nodename &optional no-going-back)
818
  (buffer-disable-undo (current-buffer))
Jim Blandy's avatar
Jim Blandy committed
819 820 821 822 823
  (or (eq major-mode 'Info-mode)
      (Info-mode))
  (widen)
  (setq Info-current-node nil)
  (unwind-protect
824 825
      (let ((case-fold-search t)
	    anchorpos)
826 827 828
        ;; Switch files if necessary
        (or (null filename)
            (equal Info-current-file filename)
829
            (let ((inhibit-read-only t))
830 831 832 833 834
              (setq Info-current-file nil
                    Info-current-subfile nil
                    Info-current-file-completions nil
                    buffer-file-name nil)
              (erase-buffer)
Jesper Harder's avatar
Jesper Harder committed
835 836 837 838 839
	      (cond
	       ((eq filename t)
		(Info-insert-dir))
	       ((eq filename 'apropos)
		(insert-buffer-substring " *info-apropos*"))
Juri Linkov's avatar
Juri Linkov committed
840 841 842 843
	       ((eq filename 'history)
		(insert-buffer-substring " *info-history*"))
	       ((eq filename 'toc)
		(insert-buffer-substring " *info-toc*"))
Jesper Harder's avatar
Jesper Harder committed
844
	       (t
845
                (info-insert-file-contents filename nil)
Jesper Harder's avatar
Jesper Harder committed
846
                (setq default-directory (file-name-directory filename))))
847
              (set-buffer-modified-p nil)
848 849 850 851 852 853

	      ;; Check makeinfo version for index cookie support
	      (let ((found nil))
		(goto-char (point-min))
		(condition-case ()
		    (if (and (re-search-forward
854
			      "makeinfo[ \n]version[ \n]\\([0-9]+.[0-9]+\\)"
855 856 857 858 859 860
			      (line-beginning-position 3) t)
			     (not (version< (match-string 1) "4.7")))
			(setq found t))
		  (error nil))
		(set (make-local-variable 'Info-file-supports-index-cookies) found))

861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882
              ;; See whether file has a tag table.  Record the location if yes.
              (goto-char (point-max))
              (forward-line -8)
              ;; Use string-equal, not equal, to ignore text props.
              (if (not (or (string-equal nodename "*")
                           (not
                            (search-forward "\^_\nEnd tag table\n" nil t))))
                  (let (pos)
                    ;; We have a tag table.  Find its beginning.
                    ;; Is this an indirect file?
                    (search-backward "\nTag table:\n")
                    (setq pos (point))
                    (if (save-excursion
                          (forward-line 2)
                          (looking-at "(Indirect)\n"))
                        ;; It is indirect.  Copy it to another buffer
                        ;; and record that the tag table is in that buffer.
                        (let ((buf (current-buffer))
                              (tagbuf
                               (or Info-tag-table-buffer
                                   (generate-new-buffer " *info tag table*"))))
                          (setq Info-tag-table-buffer tagbuf)
883
                          (with-current-buffer tagbuf
884
                            (buffer-disable-undo (current-buffer))
885 886 887 888 889 890 891 892
                            (setq case-fold-search t)
                            (erase-buffer)
                            (insert-buffer-substring buf))
                          (set-marker Info-tag-table-marker
                                      (match-end 0) tagbuf))
                      (set-marker Info-tag-table-marker pos)))
                (set-marker Info-tag-table-marker nil))
              (setq Info-current-file
Jesper Harder's avatar
Jesper Harder committed
893 894 895 896
		    (cond
		     ((eq filename t) "dir")
		     (t filename)))
	      ))
897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912
        ;; Use string-equal, not equal, to ignore text props.
        (if (string-equal nodename "*")
            (progn (setq Info-current-node nodename)
                   (Info-set-mode-line))
          ;; Possibilities:
          ;;
          ;; 1. Anchor found in tag table
          ;; 2. Anchor *not* in tag table
          ;;
          ;; 3. Node found in tag table
          ;; 4. Node *not* found in tag table, but found in file
          ;; 5. Node *not* in tag table, and *not* in file
          ;;
          ;; *Or* the same, but in an indirect subfile.

          ;; Search file for a suitable node.
913
	  (let ((guesspos (point-min))
914
		(regexp (concat "\\(Node:\\|Ref:\\) *\\("
915
				(if (stringp nodename)
916 917
				    (regexp-quote nodename)
				  "")
918
				"\\) *[,\t\n\177]")))
919

920
	    (catch 'foo
921

922
	      ;; First, search a tag table, if any
923 924 925
	      (when (marker-position Info-tag-table-marker)
		(let* ((m Info-tag-table-marker)
		       (found (Info-find-in-tag-table m regexp)))
926

927 928 929
		  (when found
		    ;; FOUND is (ANCHOR POS MODE).
		    (setq guesspos (nth 1 found))
930

931 932 933 934 935 936 937
		    ;; If this is an indirect file, determine which
		    ;; file really holds this node and read it in.
		    (unless (eq (nth 2 found) 'Info-mode)
		      ;; Note that the current buffer must be the
		      ;; *info* buffer on entry to
		      ;; Info-read-subfile.  Thus the hackery above.
		      (setq guesspos (Info-read-subfile guesspos)))
938 939

		    ;; Handle anchor
940 941 942
		    (when (nth 0 found)
		      (goto-char (setq anchorpos guesspos))
		      (throw 'foo t)))))
943 944 945 946

	      ;; Else we may have a node, which we search for:
	      (goto-char (max (point-min)
			      (- (byte-to-position guesspos) 1000)))
947

948 949 950 951 952 953 954
	      ;; Now search from our advised position (or from beg of
	      ;; buffer) to find the actual node.  First, check
	      ;; whether the node is right where we are, in case the
	      ;; buffer begins with a node.
	      (let ((pos (Info-find-node-in-buffer regexp)))
		(when pos
		  (goto-char pos)
955 956 957 958 959 960 961 962 963 964 965
		  (throw 'foo t)))

              (when (string-match "\\([^.]+\\)\\." nodename)
                (let (Info-point-loc)
                  (Info-find-node-2
                   filename (match-string 1 nodename) no-going-back))
                (widen)
                (throw 'foo t))

              ;; No such anchor in tag table or node in tag table or file
              (error "No such node or anchor: %s" nodename))
966 967

	    (Info-select-node)
Juri Linkov's avatar
Juri Linkov committed
968
	    (goto-char (point-min))
969 970 971 972
	    (forward-line 1)		       ; skip header line
	    (when (> Info-breadcrumbs-depth 0) ; skip breadcrumbs line
	      (forward-line 1))

Juri Linkov's avatar
Juri Linkov committed
973 974 975 976 977 978 979 980
	    (cond (anchorpos
                   (let ((new-history (list Info-current-file
                                            (substring-no-properties nodename))))
                     ;; Add anchors to the history too
                     (setq Info-history-list
                           (cons new-history
                                 (delete new-history Info-history-list))))
                   (goto-char anchorpos))
981 982 983 984 985 986
                  ((numberp Info-point-loc)
                   (forward-line (1- Info-point-loc))
                   (setq Info-point-loc nil))
		  ((stringp Info-point-loc)
		   (Info-find-index-name Info-point-loc)
		   (setq Info-point-loc nil))))))
Jim Blandy's avatar
Jim Blandy committed
987 988
    ;; If we did not finish finding the specified node,
    ;; go back to the previous one.
989
    (or Info-current-node no-going-back (null Info-history)
990 991 992 993
        (let ((hist (car Info-history)))
          (setq Info-history (cdr Info-history))
          (Info-find-node (nth 0 hist) (nth 1 hist) t)
          (goto-char (nth 2 hist))))))
Jim Blandy's avatar
Jim Blandy committed
994

995 996
;; Cache the contents of the (virtual) dir file, once we have merged
;; it for the first time, so we can save time subsequently.
997 998
(defvar Info-dir-contents nil)

999 1000 1001 1002
;; Cache for the directory we decided to use for the default-directory
;; of the merged dir text.
(defvar Info-dir-contents-directory nil)

1003 1004 1005 1006
;; Record the file attributes of all the files from which we
;; constructed Info-dir-contents.
(defvar Info-dir-file-attributes nil)

1007 1008
(defvar Info-dir-file-name nil)

1009
;; Construct the Info directory node by merging the files named `dir'
1010 1011 1012
;; from various directories.  Set the *info* buffer's
;; default-directory to the first directory we actually get any text
;; from.
1013
(defun Info-insert-dir ()
1014 1015 1016 1017
  (if (and Info-dir-contents Info-dir-file-attributes
	   ;; Verify that none of the files we used has changed
	   ;; since we used it.
	   (eval (cons 'and
1018 1019 1020 1021 1022 1023