lisp/info-xref.el

   1 ;;; info-xref.el --- check external references in an Info document
   2
   3 ;; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
   4 ;;   Free Software Foundation, Inc.
   5
   6 ;; Author: Kevin Ryde <user42@zip.com.au>
   7 ;; Keywords: docs
   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 3 of the License, or
  14 ;; (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; This file implements some simple checking of external cross references in
  27 ;; info files, by attempting to visit the nodes specified.
  28 ;;
  29 ;; "makeinfo" checks references internal to a document, but not external
  30 ;; references, which makes it rather easy for mistakes to creep in or node
  31 ;; name changes to go unnoticed.  `Info-validate' doesn't check external
  32 ;; references either.
  33 ;;
  34 ;; `M-x info-xref-check' checks one file.  When invoked from an Info-mode or
  35 ;; texinfo-mode buffer, the current info file is the default at the prompt.
  36 ;;
  37 ;; `M-x info-xref-check-all' looks at everything in the normal info path.
  38 ;; This might be a lot of files but it's a good way to check the consistency
  39 ;; of the whole system.
  40 ;;
  41 ;; Results are shown in a buffer.  The format is a bit rough, but hopefully
  42 ;; there won't be too many problems normally, and correcting them is a
  43 ;; manual process anyway, a case of finding the right spot in the original
  44 ;; .texi and finding what node it ought to point to.
  45 ;;
  46 ;; When a target info file doesn't exist there's clearly no way to validate
  47 ;; node references within it.  A message is given for missing target files
  48 ;; (once per source document), it could be simply that the target hasn't
  49 ;; been installed, or it could be a mistake in the reference.
  50 ;;
  51 ;; Indirect info files are understood, just pass the top-level foo.info to
  52 ;; `info-xref-check' and it traverses all sub-files.  Compressed info files
  53 ;; are accepted too, as usual for `Info-mode'.
  54 ;;
  55 ;; `info-xref-check-all' is rather permissive in what it considers an info
  56 ;; file.  It has to be since info files don't necessarily have a ".info"
  57 ;; suffix (eg. this is usual for the emacs manuals).  One consequence of
  58 ;; this is that if for instance there's a source code directory in
  59 ;; `Info-directory-list' then a lot of extraneous files might be read, which
  60 ;; will be time consuming but should be harmless.
  61 ;;
  62 ;; `M-x info-xref-check-all-custom' is a related command, it goes through
  63 ;; all info document references in customizable variables, checking them
  64 ;; like info file cross references.
  65
  66 ;;; Code:
  67
  68 (require 'info)
  69
  70 (defconst info-xref-results-buffer "*info-xref results*"
  71   "Name of the buffer for info-xref results.")
  72
  73 ;;;###autoload
  74 (defun info-xref-check (filename)
  75   "Check external references in FILENAME, an info document."
  76   (interactive
  77    (list
  78     (let* ((default-filename
  79              (cond ((eq major-mode 'Info-mode)
  80                     Info-current-file)
  81                    ((eq major-mode 'texinfo-mode)
  82                     ;; look for @setfilename like makeinfo.el does
  83                     (save-excursion
  84                       (goto-char (point-min))
  85                       (if (re-search-forward
  86                            "^@setfilename[ \t]+\\([^ \t\n]+\\)[ \t]*"
  87                            (line-beginning-position 100) t)
  88                           (expand-file-name (match-string 1)))))))
  89            (prompt (if default-filename
  90                        (format "Info file (%s): " default-filename)
  91                      "Info file: ")))
  92       (read-file-name prompt nil default-filename t))))
  93   (info-xref-check-list (list filename)))
  94
  95 ;;;###autoload
  96 (defun info-xref-check-all ()
  97   "Check external references in all info documents in the usual path.
  98 The usual path is `Info-directory-list' and `Info-additional-directory-list'."
  99   (interactive)
 100   (info-xref-check-list (info-xref-all-info-files)))
 101
 102 ;; An alternative to trying to get only top-level files here would be to
 103 ;; simply return all files, and have info-xref-check-list not follow
 104 ;; Indirect:.  The current way seems a bit nicer though, because it gets the
 105 ;; proper top-level filename into the error messages, and suppresses
 106 ;; duplicate "not available" messages for all subfiles of a single document.
 107
 108 (defun info-xref-all-info-files ()
 109   "Return a list of all available info files.
 110 Only top-level files are returned, subfiles are excluded.
 111
 112 Since info files don't have to have a .info suffix, all files in the
 113 relevant directories are considered, which might mean a lot of extraneous
 114 things are returned if for instance a source code directory is in the path."
 115
 116   (info-initialize) ;; establish Info-directory-list
 117   (apply 'nconc
 118          (mapcar
 119           (lambda (dir)
 120             (let ((result nil))
 121               (dolist (name (directory-files dir t))
 122                 (unless (or (file-directory-p name) (info-xref-subfile-p name))
 123                   (push name result)))
 124               (nreverse result)))
 125           (append Info-directory-list Info-additional-directory-list))))
 126
 127 (defun info-xref-subfile-p (filename)
 128   "Return t if FILENAME is an info subfile.
 129 If removing the last \"-<NUM>\" from the filename gives a file that exists,
 130 then consider FILENAME a subfile.  This is an imperfect test, we probably
 131 should open up the purported top file and see what subfiles it says."
 132   (and (string-match "\\`\\(\\([^-]*-\\)*[^-]*\\)-[0-9]+\\(.*\\)\\'" filename)
 133        (file-exists-p (concat (match-string 1 filename)
 134                               (match-string 3 filename)))))
 135
 136
 137 ;; Some dynamic variables are used to share information with sub-functions
 138 ;; below.
 139 ;;
 140 ;; info-xref-filename-header - a heading message for the current top-level
 141 ;;     filename, or "" when it's been printed.
 142 ;;
 143 (defvar info-xref-xfile-alist)
 144 ;;
 145 ;; info-xref-good - count of good cross references.
 146 ;;
 147 (defvar info-xref-good)
 148 ;;
 149 ;; info-xref-bad - count of bad cross references.
 150 ;;
 151 (defvar info-xref-bad)
 152 ;;
 153 ;; info-xref-xfile-alist - indexed by "(foo)" with value nil or t according
 154 ;;     to whether "(foo)" exists or not.  This is used to suppress duplicate
 155 ;;     messages about foo not being available.  (Duplicates within one
 156 ;;     top-level file that is.)
 157 ;;
 158 (defvar info-xref-filename-heading)
 159
 160 (defun info-xref-check-list (filename-list)
 161   "Check external references in info documents in FILENAME-LIST."
 162   (pop-to-buffer info-xref-results-buffer t)
 163   (erase-buffer)
 164   (let ((info-xref-good 0)
 165         (info-xref-bad  0))
 166     (dolist (info-xref-filename filename-list)
 167       (let ((info-xref-filename-heading
 168              (format "In file %s:\n" info-xref-filename))
 169             (info-xref-xfile-alist nil))
 170         (with-temp-message (format "Looking at %s" info-xref-filename)
 171           (with-temp-buffer
 172             (info-insert-file-contents info-xref-filename)
 173             (goto-char (point-min))
 174             (if (re-search-forward "\^_\nIndirect:\n" nil t)
 175                 (let ((dir (file-name-directory info-xref-filename)))
 176                   (while (looking-at "\\(.*\\): [0-9]+\n")
 177                     (let ((subfile (match-string 1)))
 178                       (with-temp-buffer
 179                         (info-insert-file-contents
 180                          (expand-file-name subfile dir))
 181                         (info-xref-check-buffer)))
 182                     (forward-line)))
 183               (info-xref-check-buffer))))))
 184     (insert (format "done, %d good, %d bad\n" info-xref-good info-xref-bad))))
 185
 186 (defun info-xref-check-buffer ()
 187   "Check external references in the info file in the current buffer.
 188 This should be the raw file contents, not `Info-mode'."
 189   (goto-char (point-min))
 190   (while (re-search-forward
 191           "\\*[Nn]ote[ \n\t]+[^:]*:[ \n\t]+\\(\\(([^)]*)\\)[^.,]+\\)[.,]"
 192           nil t)
 193     (let* ((file (match-string 2))
 194            (node ;; Canonicalize spaces: we could use "[\t\n ]+" but
 195             ;; we try to avoid uselessly replacing " " with " ".
 196             (replace-regexp-in-string "[\t\n][\t\n ]*\\| [\t\n ]+" " "
 197                                       (match-string 1) t t)))
 198       (if (string-equal "()" file)
 199           (info-xref-output "Empty filename part: %s\n" node)
 200         ;; see if the file exists, if we haven't tried it before
 201         (unless (assoc file info-xref-xfile-alist)
 202           (let ((found (info-xref-goto-node-p file)))
 203             (push (cons file found) info-xref-xfile-alist)
 204             (unless found
 205               (info-xref-output "Not available to check: %s\n" file))))
 206         ;; if the file exists, try the node
 207         (when (cdr (assoc file info-xref-xfile-alist))
 208           (if (info-xref-goto-node-p node)
 209               (setq info-xref-good (1+ info-xref-good))
 210             (setq info-xref-bad (1+ info-xref-bad))
 211             (info-xref-output "No such node: %s\n" node)))))))
 212
 213 (defun info-xref-output (str &rest args)
 214   "Emit a `format'-ed message STR+ARGS to the info-xref output buffer."
 215   (with-current-buffer info-xref-results-buffer
 216     (insert info-xref-filename-heading
 217             (apply 'format str args))
 218     (setq info-xref-filename-heading "")
 219     ;; all this info-xref can be pretty slow, display now so the user can
 220     ;; see some progress
 221     (sit-for 0)))
 222
 223 ;; When asking Info-goto-node to fork, *info* needs to be the current
 224 ;; buffer, otherwise it seems to clone the current buffer but then do the
 225 ;; goto-node in plain *info*.
 226 ;;
 227 ;; We only fork if *info* already exists, if it doesn't then we can create
 228 ;; and destroy just that instead of a new name.
 229 ;;
 230 ;; If Info-goto-node can't find the file, then no new buffer is created.  If
 231 ;; it finds the file but not the node, then a buffer is created.  Handle
 232 ;; this difference by checking before killing.
 233 ;;
 234 (defun info-xref-goto-node-p (node)
 235   "Return t if it's possible to go to the given NODE."
 236   (let ((oldbuf (current-buffer)))
 237     (save-excursion
 238       (save-window-excursion
 239         (prog1
 240             (condition-case err
 241                 (progn
 242                   (Info-goto-node node
 243                                   (when (get-buffer "*info*")
 244                                     (set-buffer "*info*")
 245                                     "xref - temporary"))
 246                   t)
 247               (error nil))
 248           (unless (equal (current-buffer) oldbuf)
 249             (kill-buffer (current-buffer))))))))
 250
 251 ;;;###autoload
 252 (defun info-xref-check-all-custom ()
 253   "Check info references in all customize groups and variables.
 254 `custom-manual' and `info-link' entries in the `custom-links' list are checked.
 255
 256 `custom-load' autoloads for all symbols are loaded in order to get all the
 257 link information.  This will be a lot of lisp packages loaded, and can take
 258 quite a while."
 259
 260   (interactive)
 261   (pop-to-buffer info-xref-results-buffer t)
 262   (erase-buffer)
 263   (let ((info-xref-filename-heading ""))
 264
 265     ;; `custom-load-symbol' is not used, since it quietly ignores errors,
 266     ;; but we want to show them (since they may mean incomplete checking).
 267     ;;
 268     ;; Just one pass through mapatoms is made.  There shouldn't be any new
 269     ;; custom-loads setup by packages loaded.
 270     ;;
 271     (info-xref-output "Loading custom-load autoloads ...\n")
 272     (require 'cus-start)
 273     (require 'cus-load)
 274     (let ((viper-mode nil)) ;; tell viper.el not to ask about viperizing
 275       (mapatoms
 276        (lambda (symbol)
 277          (dolist (load (get symbol 'custom-loads))
 278            (cond ((symbolp load)
 279                   (condition-case cause (require load)
 280                     (error
 281                      (info-xref-output "Symbol `%s': cannot require '%s: %s\n"
 282                                        symbol load cause))))
 283                  ;; skip if previously loaded
 284                  ((assoc load load-history))
 285                  ((assoc (locate-library load) load-history))
 286                  (t
 287                   (condition-case cause (load load)
 288                     (error
 289                      (info-xref-output "Symbol `%s': cannot load \"%s\": %s\n"
 290                                        symbol load cause)))))))))
 291
 292     ;; Don't bother to check whether the info file exists as opposed to just
 293     ;; a missing node.  If you have the lisp then you should have the
 294     ;; documentation, so missing node name will be the usual fault.
 295     ;;
 296     (info-xref-output "\nChecking custom-links references ...\n")
 297     (let ((good 0)
 298           (bad  0))
 299       (mapatoms
 300        (lambda (symbol)
 301          (dolist (link (get symbol 'custom-links))
 302            (when (memq (car link) '(custom-manual info-link))
 303              ;; skip :tag part of (custom-manual :tag "Foo" "(foo)Node")
 304              (if (eq :tag (cadr link))
 305                  (setq link (cddr link)))
 306              (if (info-xref-goto-node-p (cadr link))
 307                  (setq good (1+ good))
 308                (setq bad (1+ bad))
 309                ;; symbol-file gives nil for preloaded variables, would need
 310                ;; to copy what describe-variable does to show the right place
 311                (info-xref-output "Symbol `%s' (in %s): cannot goto node: %s\n"
 312                                  symbol (symbol-file symbol) (cadr link)))))))
 313       (info-xref-output "%d good, %d bad\n" good bad))))
 314
 315 (provide 'info-xref)
 316
 317 ;;; info-xref.el ends here