lisp/mail/rnews.el

   1 ;;; rnews.el --- USENET news reader for gnu emacs
   2
   3 ;; Copyright (C) 1985, 1986, 1987 Free Software Foundation, Inc.
   4
   5 ;; Maintainer: FSF
   6 ;; Keywords: news
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software; you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation; either version 2, or (at your option)
  13 ;; any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  22 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  23 ;; Boston, MA 02111-1307, USA.
  24
  25 ;;; Change Log:
  26
  27 ;; Created Sun Mar 10,1985 at 21:35:01 ads and sundar@hernes.ai.mit.edu
  28 ;; Should do the point pdl stuff sometime
  29 ;; finito except pdl.... Sat Mar 16,1985 at 06:43:44
  30 ;; lets keep the summary stuff out until we get it working ..
  31 ;;      sundar@hermes.ai.mit.edu Wed Apr 10,1985 at 16:32:06
  32 ;; hack slash maim. mly@gnu.org Thu 18 Apr, 1985 06:11:14
  33 ;; modified to correct reentrance bug, to not bother with groups that
  34 ;;   received no new traffic since last read completely, to find out
  35 ;;   what traffic a group has available much more quickly when
  36 ;;   possible, to do some completing reads for group names - should
  37 ;;   be much faster...
  38 ;;      KING@KESTREL.arpa, Thu Mar 13 09:03:28 1986
  39 ;; made news-{next,previous}-group skip groups with no new messages; and
  40 ;; added checking for unsubscribed groups to news-add-news-group
  41 ;;      tower@gnu.org Jul 18 1986
  42 ;; bound rmail-output to C-o; and changed header-field commands binding to
  43 ;; agree with the new C-c C-f usage in sendmail
  44 ;;      tower@gnu.org Sep  3 1986
  45 ;; added news-rotate-buffer-body
  46 ;;      tower@gnu.org Oct 17 1986
  47 ;; made messages more user friendly, cleaned up news-inews
  48 ;; move posting and mail code to new file rnewpost.el
  49 ;;      tower@gnu.org Oct 29 1986
  50 ;; added caesar-region, rename news-caesar-buffer-body, hacked accordingly
  51 ;;      tower@gnu.org Nov 21 1986
  52 ;; added tower@gnu.org 22 Apr 87
  53
  54 ;;; Code:
  55
  56 (require 'mail-utils)
  57 (require 'sendmail)
  58
  59 (autoload 'rmail-output "rmailout"
  60   "Append this message to Unix mail file named FILE-NAME."
  61   t)
  62
  63 (autoload 'news-reply "rnewspost"
  64   "Compose and post a reply to the current article on USENET.
  65 While composing the reply, use \\[mail-yank-original] to yank the original
  66 message into it."
  67   t)
  68
  69 (autoload 'news-mail-other-window "rnewspost"
  70   "Send mail in another window.
  71 While composing the message, use \\[mail-yank-original] to yank the
  72 original message into it."
  73   t)
  74
  75 (autoload 'news-post-news "rnewspost"
  76   "Begin editing a new USENET news article to be posted."
  77   t)
  78
  79 (autoload 'news-mail-reply "rnewspost"
  80   "Mail a reply to the author of the current article.
  81 While composing the reply, use \\[mail-yank-original] to yank the original
  82 message into it."
  83   t)
  84
  85 (defvar news-group-hook-alist nil
  86   "Alist of (GROUP-REGEXP . HOOK) pairs.
  87 Just before displaying a message, each HOOK is called
  88 if its GROUP-REGEXP matches the current newsgroup name.")
  89
  90 (defvar rmail-last-file (expand-file-name "~/mbox.news"))
  91
  92 ;Now in paths.el.
  93 ;(defvar news-path "/usr/spool/news/"
  94 ;  "The root directory below which all news files are stored.")
  95
  96 (defvar news-startup-file "$HOME/.newsrc" "Contains ~/.newsrc")
  97 (defvar news-certification-file "$HOME/.news-dates" "Contains ~/.news-dates")
  98
  99 ;; random headers that we decide to ignore.
 100 (defvar news-ignored-headers
 101   "^Path:\\|^Posting-Version:\\|^Article-I.D.:\\|^Expires:\\|^Date-Received:\\|^References:\\|^Control:\\|^Xref:\\|^Lines:\\|^Posted:\\|^Relay-Version:\\|^Message-ID:\\|^Nf-ID:\\|^Nf-From:\\|^Approved:\\|^Sender:"
 102   "All random fields within the header of a message.")
 103
 104 (defvar news-mode-map nil)
 105 (defvar news-read-first-time-p t)
 106 ;; Contains the (dotified) news groups of which you are a member.
 107 (defvar news-user-group-list nil)
 108
 109 (defvar news-current-news-group nil)
 110 (defvar news-current-group-begin nil)
 111 (defvar news-current-group-end  nil)
 112 (defvar news-current-certifications nil
 113         "An assoc list of a group name and the time at which it is
 114 known that the group had no new traffic")
 115 (defvar news-current-certifiable nil
 116         "The time when the directory we are now working on was written")
 117
 118 (defvar news-message-filter nil
 119   "User specifiable filter function that will be called during
 120 formatting of the news file")
 121
 122 ;(defvar news-mode-group-string "Starting-Up"
 123 ;  "Mode line group name info is held in this variable")
 124 (defvar news-list-of-files nil
 125   "Global variable in which we store the list of files
 126 associated with the current newsgroup")
 127 (defvar news-list-of-files-possibly-bogus nil
 128   "variable indicating we only are guessing at which files are available.
 129 Not currently used.")
 130
 131 ;; association list in which we store lists of the form
 132 ;; (pointified-group-name (first last old-last))
 133 (defvar news-group-article-assoc nil)
 134
 135 (defvar news-current-message-number 0 "Displayed Article Number")
 136 (defvar news-total-current-group 0 "Total no of messages in group")
 137
 138 (defvar news-unsubscribe-groups ())
 139 (defvar news-point-pdl () "List of visited news messages.")
 140 (defvar news-no-jumps-p t)
 141 (defvar news-buffer () "Buffer into which news files are read.")
 142
 143 (defmacro news-push (item ref)
 144   (list 'setq ref (list 'cons item ref)))
 145
 146 (defmacro news-cadr (x) (list 'car (list 'cdr x)))
 147 (defmacro news-cdar (x) (list 'cdr (list 'car x)))
 148 (defmacro news-caddr (x) (list 'car (list 'cdr (list 'cdr x))))
 149 (defmacro news-cadar (x) (list 'car (list 'cdr (list 'car x))))
 150 (defmacro news-caadr (x) (list 'car (list 'car (list 'cdr x))))
 151 (defmacro news-cdadr (x) (list 'cdr (list 'car (list 'cdr x))))
 152
 153 (defmacro news-wins (pfx index)
 154   `(file-exists-p (concat ,pfx "/" (int-to-string ,index))))
 155
 156 (defvar news-max-plausible-gap 2
 157         "* In an rnews directory, the maximum possible gap size.
 158 A gap is a sequence of missing messages between two messages that exist.
 159 An empty file does not contribute to a gap -- it ends one.")
 160
 161 (defun news-find-first-and-last (prefix base)
 162   (and (news-wins prefix base)
 163        (cons (news-find-first-or-last prefix base -1)
 164              (news-find-first-or-last prefix base 1))))
 165
 166 (defmacro news-/ (a1 a2)
 167 ;; a form of / that guarantees that (/ -1 2) = 0
 168   (if (zerop (/ -1 2))
 169       `(/ ,a1 ,a2)
 170     `(if (< ,a1 0)
 171          (- (/ (- ,a1) ,a2))
 172        (/ ,a1 ,a2))))
 173
 174 (defun news-find-first-or-last (pfx base dirn)
 175   ;; first use powers of two to find a plausible ceiling
 176   (let ((original-dir dirn))
 177     (while (news-wins pfx (+ base dirn))
 178       (setq dirn (* dirn 2)))
 179     (setq dirn (news-/ dirn 2))
 180     ;; Then use a binary search to find the high water mark
 181     (let ((offset (news-/ dirn 2)))
 182       (while (/= offset 0)
 183         (if (news-wins pfx (+ base dirn offset))
 184             (setq dirn (+ dirn offset)))
 185         (setq offset (news-/ offset 2))))
 186     ;; If this high-water mark is bogus, recurse.
 187     (let ((offset (* news-max-plausible-gap original-dir)))
 188       (while (and (/= offset 0) (not (news-wins pfx (+ base dirn offset))))
 189         (setq offset (- offset original-dir)))
 190       (if (= offset 0)
 191           (+ base dirn)
 192         (news-find-first-or-last pfx (+ base dirn offset) original-dir)))))
 193
 194 (defun rnews ()
 195 "Read USENET news for groups for which you are a member and add or
 196 delete groups.
 197 You can reply to articles posted and send articles to any group.
 198
 199 Type \\[describe-mode] once reading news to get a list of rnews commands."
 200   (interactive)
 201   (let ((last-buffer (buffer-name)))
 202     (make-local-variable 'rmail-last-file)
 203     (switch-to-buffer (setq news-buffer (get-buffer-create "*news*")))
 204     (news-mode)
 205     (setq news-buffer-save last-buffer)
 206     (setq buffer-read-only nil)
 207     (erase-buffer)
 208     (setq buffer-read-only t)
 209     (set-buffer-modified-p t)
 210     (sit-for 0)
 211     (message "Getting new USENET news...")
 212     (news-set-mode-line)
 213     (news-get-certifications)
 214     (news-get-new-news)))
 215
 216 (defun news-group-certification (group)
 217   (cdr-safe (assoc group news-current-certifications)))
 218
 219
 220 (defun news-set-current-certifiable ()
 221   ;; Record the date that corresponds to the directory you are about to check
 222   (let ((file (concat news-path
 223                       (string-subst-char ?/ ?. news-current-news-group))))
 224     (setq news-current-certifiable
 225           (nth 5 (file-attributes
 226                   (or (file-symlink-p file) file))))))
 227
 228 (defun news-get-certifications ()
 229   ;; Read the certified-read file from last session
 230   (save-excursion
 231     (save-window-excursion
 232       (setq news-current-certifications
 233             (car-safe
 234              (condition-case var
 235                  (let*
 236                      ((file (substitute-in-file-name news-certification-file))
 237                       (buf (find-file-noselect file)))
 238                    (and (file-exists-p file)
 239                         (progn
 240                           (switch-to-buffer buf 'norecord)
 241                           (unwind-protect
 242                               (read-from-string (buffer-string))
 243                             (kill-buffer buf)))))
 244                (error nil)))))))
 245
 246 (defun news-write-certifications ()
 247   ;; Write a certification file.
 248   ;; This is an assoc list of group names with doubletons that represent
 249   ;; mod times of the directory when group is read completely.
 250   (save-excursion
 251     (save-window-excursion
 252       (with-output-to-temp-buffer
 253           "*CeRtIfIcAtIoNs*"
 254           (print news-current-certifications))
 255       (let ((buf (get-buffer "*CeRtIfIcAtIoNs*")))
 256         (switch-to-buffer buf)
 257         (write-file (substitute-in-file-name news-certification-file))
 258         (kill-buffer buf)))))
 259
 260 (defun news-set-current-group-certification ()
 261   (let ((cgc (assoc news-current-news-group news-current-certifications)))
 262     (if cgc (setcdr cgc news-current-certifiable)
 263       (news-push (cons news-current-news-group news-current-certifiable)
 264                  news-current-certifications))))
 265
 266 (defun news-set-minor-modes ()
 267   "Creates a minor mode list that has group name, total articles,
 268 and attribute for current article."
 269   (setq news-minor-modes (list (cons 'foo
 270                                      (concat news-current-message-number
 271                                              "/"
 272                                              news-total-current-group
 273                                              (news-get-attribute-string)))))
 274   ;; Detect Emacs versions 18.16 and up, which display
 275   ;; directly from news-minor-modes by using a list for mode-name.
 276   (or (boundp 'minor-mode-alist)
 277       (setq minor-modes news-minor-modes)))
 278
 279 (defun news-set-message-counters ()
 280   "Scan through current news-groups filelist to figure out how many messages
 281 are there. Set counters for use with minor mode display."
 282     (if (null news-list-of-files)
 283         (setq news-current-message-number 0)))
 284
 285 (if news-mode-map
 286     nil
 287   (setq news-mode-map (make-keymap))
 288   (suppress-keymap news-mode-map)
 289   (define-key news-mode-map "." 'beginning-of-buffer)
 290   (define-key news-mode-map " " 'scroll-up)
 291   (define-key news-mode-map "\177" 'scroll-down)
 292   (define-key news-mode-map "n" 'news-next-message)
 293   (define-key news-mode-map "c" 'news-make-link-to-message)
 294   (define-key news-mode-map "p" 'news-previous-message)
 295   (define-key news-mode-map "j" 'news-goto-message)
 296   (define-key news-mode-map "q" 'news-exit)
 297   (define-key news-mode-map "e" 'news-exit)
 298   (define-key news-mode-map "\ej" 'news-goto-news-group)
 299   (define-key news-mode-map "\en" 'news-next-group)
 300   (define-key news-mode-map "\ep" 'news-previous-group)
 301   (define-key news-mode-map "l" 'news-list-news-groups)
 302   (define-key news-mode-map "?" 'describe-mode)
 303   (define-key news-mode-map "g" 'news-get-new-news)
 304   (define-key news-mode-map "f" 'news-reply)
 305   (define-key news-mode-map "m" 'news-mail-other-window)
 306   (define-key news-mode-map "a" 'news-post-news)
 307   (define-key news-mode-map "r" 'news-mail-reply)
 308   (define-key news-mode-map "o" 'news-save-item-in-file)
 309   (define-key news-mode-map "\C-o" 'rmail-output)
 310   (define-key news-mode-map "t" 'news-show-all-headers)
 311   (define-key news-mode-map "x" 'news-force-update)
 312   (define-key news-mode-map "A" 'news-add-news-group)
 313   (define-key news-mode-map "u" 'news-unsubscribe-current-group)
 314   (define-key news-mode-map "U" 'news-unsubscribe-group)
 315   (define-key news-mode-map "\C-c\C-r" 'news-caesar-buffer-body))
 316
 317 (defun news-mode ()
 318   "News Mode is used by M-x rnews for reading USENET Newsgroups articles.
 319 New readers can find additional help in newsgroup: news.announce.newusers .
 320 All normal editing commands are turned off.
 321 Instead, these commands are available:
 322
 323 .       move point to front of this news article (same as Meta-<).
 324 Space   scroll to next screen of this news article.
 325 Delete  scroll down previous page of this news article.
 326 n       move to next news article, possibly next group.
 327 p       move to previous news article, possibly previous group.
 328 j       jump to news article specified by numeric position.
 329 M-j     jump to news group.
 330 M-n     goto next news group.
 331 M-p     goto previous news group.
 332 l       list all the news groups with current status.
 333 ?       print this help message.
 334 C-c C-r caesar rotate all letters by 13 places in the article's body (rot13).
 335 g       get new USENET news.
 336 f       post a reply article to USENET.
 337 a       post an original news article.
 338 A       add a newsgroup.
 339 o       save the current article in the named file (append if file exists).
 340 C-o     output this message to a Unix-format mail file (append it).
 341 c       \"copy\" (actually link) current or prefix-arg msg to file.
 342         warning: target directory and message file must be on same device
 343                 (UNIX magic)
 344 t       show all the headers this news article originally had.
 345 q       quit reading news after updating .newsrc file.
 346 e       exit updating .newsrc file.
 347 m       mail a news article.  Same as C-x 4 m.
 348 x       update last message seen to be the current message.
 349 r       mail a reply to this news article.  Like m but initializes some fields.
 350 u       unsubscribe from current newsgroup.
 351 U       unsubscribe from specified newsgroup."
 352   (interactive)
 353   (kill-all-local-variables)
 354   (make-local-variable 'news-read-first-time-p)
 355   (setq news-read-first-time-p t)
 356   (make-local-variable 'news-current-news-group)
 357 ;  (setq news-current-news-group "??")
 358   (make-local-variable 'news-current-group-begin)
 359   (setq news-current-group-begin 0)
 360   (make-local-variable 'news-current-message-number)
 361   (setq news-current-message-number 0)
 362   (make-local-variable 'news-total-current-group)
 363   (make-local-variable 'news-buffer-save)
 364   (make-local-variable 'version-control)
 365   (setq version-control 'never)
 366   (make-local-variable 'news-point-pdl)
 367 ;  This breaks it.  I don't have time to figure out why. -- RMS
 368 ;  (make-local-variable 'news-group-article-assoc)
 369   (setq major-mode 'news-mode)
 370   (setq mode-line-process '(news-minor-modes))
 371   (setq mode-name "NEWS")
 372   (news-set-mode-line)
 373   (set-syntax-table text-mode-syntax-table)
 374   (use-local-map news-mode-map)
 375   (setq local-abbrev-table text-mode-abbrev-table)
 376   (run-hooks 'news-mode-hook))
 377
 378 (defun string-subst-char (new old string)
 379   (let (index)
 380     (setq old (regexp-quote (char-to-string old))
 381           string (substring string 0))
 382     (while (setq index (string-match old string))
 383       (aset string index new)))
 384   string)
 385
 386 ;; update read message number
 387 (defmacro news-update-message-read (ngroup nno)
 388   (list 'setcar
 389         (list 'news-cdadr
 390               (list 'assoc ngroup 'news-group-article-assoc))
 391         nno))
 392
 393 (defun news-parse-range (number-string)
 394   "Parse string representing range of numbers of he form <a>-<b>
 395 to a list (a . b)"
 396   (let ((n (string-match "-" number-string)))
 397     (if n
 398         (cons (string-to-int (substring number-string 0 n))
 399               (string-to-int (substring number-string (1+ n))))
 400       (setq n (string-to-int number-string))
 401       (cons n n))))
 402
 403 ;(defun is-in (elt lis)
 404 ;  (catch 'foo
 405 ;    (while lis
 406 ;      (if (equal (car lis) elt)
 407 ;         (throw 'foo t)
 408 ;       (setq lis (cdr lis))))))
 409
 410 (defun news-get-new-news ()
 411   "Get new USENET news, if there is any for the current user."
 412   (interactive)
 413   (if (not (null news-user-group-list))
 414       (news-update-newsrc-file))
 415   (setq news-group-article-assoc ())
 416   (setq news-user-group-list ())
 417   (message "Looking up %s file..." news-startup-file)
 418   (let ((file (substitute-in-file-name news-startup-file))
 419         (temp-user-groups ()))
 420     (save-excursion
 421       (let ((newsrcbuf (find-file-noselect file))
 422             start end endofline tem)
 423         (set-buffer newsrcbuf)
 424         (goto-char 0)
 425         (while (search-forward ": " nil t)
 426           (setq end (point))
 427           (beginning-of-line)
 428           (setq start (point))
 429           (end-of-line)
 430           (setq endofline (point))
 431           (setq tem (buffer-substring start (- end 2)))
 432           (let ((range (news-parse-range
 433                         (buffer-substring end endofline))))
 434             (if (assoc tem news-group-article-assoc)
 435                 (message "You are subscribed twice to %s; I ignore second"
 436                          tem)
 437               (setq temp-user-groups (cons tem temp-user-groups)
 438                     news-group-article-assoc
 439                     (cons (list tem (list (car range)
 440                                           (cdr range)
 441                                           (cdr range)))
 442                           news-group-article-assoc)))))
 443         (kill-buffer newsrcbuf)))
 444     (setq temp-user-groups (nreverse temp-user-groups))
 445     (message "Prefrobnicating...")
 446     (switch-to-buffer news-buffer)
 447     (setq news-user-group-list temp-user-groups)
 448     (while (and temp-user-groups
 449                 (not (news-read-files-into-buffer
 450                       (car temp-user-groups) nil)))
 451       (setq temp-user-groups (cdr temp-user-groups)))
 452     (if (null temp-user-groups)
 453         (message "No news is good news.")
 454       (message ""))))
 455
 456 (defun news-list-news-groups ()
 457   "Display all the news groups to which you belong."
 458   (interactive)
 459   (with-output-to-temp-buffer "*Newsgroups*"
 460     (save-excursion
 461       (set-buffer standard-output)
 462       (insert
 463         "News Group        Msg No.       News Group        Msg No.\n")
 464       (insert
 465         "-------------------------       -------------------------\n")
 466       (let ((temp news-user-group-list)
 467             (flag nil))
 468         (while temp
 469           (let ((item (assoc (car temp) news-group-article-assoc)))
 470             (insert (car item))
 471             (indent-to (if flag 52 20))
 472             (insert (int-to-string (news-cadr (news-cadr item))))
 473             (if flag
 474                 (insert "\n")
 475               (indent-to 33))
 476             (setq temp (cdr temp) flag (not flag))))))))
 477
 478 ;; Mode line hack
 479 (defun news-set-mode-line ()
 480   "Set mode line string to something useful."
 481   (setq mode-line-process
 482         (concat " "
 483                 (if (integerp news-current-message-number)
 484                     (int-to-string news-current-message-number)
 485                  "??")
 486                 "/"
 487                 (if (integerp news-current-group-end)
 488                     (int-to-string news-current-group-end)
 489                   news-current-group-end)))
 490   (setq mode-line-buffer-identification
 491         (concat "NEWS: "
 492                 news-current-news-group
 493                 ;; Enough spaces to pad group name to 17 positions.
 494                 (substring "                 "
 495                            0 (max 0 (- 17 (length news-current-news-group))))))
 496   (set-buffer-modified-p t)
 497   (sit-for 0))
 498
 499 (defun news-goto-news-group (gp)
 500   "Takes a string and goes to that news group."
 501   (interactive (list (completing-read "NewsGroup: "
 502                                       news-group-article-assoc)))
 503   (message "Jumping to news group %s..." gp)
 504   (news-select-news-group gp)
 505   (message "Jumping to news group %s... done." gp))
 506
 507 (defun news-select-news-group (gp)
 508   (let ((grp (assoc gp news-group-article-assoc)))
 509     (if (null grp)
 510         (error "Group %s not subscribed to" gp)
 511       (progn
 512         (news-update-message-read news-current-news-group
 513                                   (news-cdar news-point-pdl))
 514         (news-read-files-into-buffer  (car grp) nil)
 515         (news-set-mode-line)))))
 516
 517 (defun news-goto-message (arg)
 518   "Goes to the article ARG in current newsgroup."
 519   (interactive "p")
 520   (if (null current-prefix-arg)
 521       (setq arg (read-no-blanks-input "Go to article: " "")))
 522   (news-select-message arg))
 523
 524 (defun news-select-message (arg)
 525   (if (stringp arg) (setq arg (string-to-int arg)))
 526   (let ((file (concat news-path
 527                       (string-subst-char ?/ ?. news-current-news-group)
 528                       "/" arg)))
 529     (if (= arg
 530            (or (news-cadr (memq (news-cdar news-point-pdl) news-list-of-files))
 531                0))
 532         (setcdr (car news-point-pdl) arg))
 533     (setq news-current-message-number arg)
 534     (if (file-exists-p file)
 535         (let ((buffer-read-only nil))
 536           (news-read-in-file file)
 537           (news-set-mode-line))
 538       (news-set-mode-line)
 539       (error "Article %d nonexistent" arg))))
 540
 541 (defun news-force-update ()
 542   "updates the position of last article read in the current news group"
 543   (interactive)
 544   (setcdr (car news-point-pdl) news-current-message-number)
 545   (message "Updated to %d" news-current-message-number))
 546
 547 (defun news-next-message (arg)
 548   "Move ARG messages forward within one newsgroup.
 549 Negative ARG moves backward.
 550 If ARG is 1 or -1, moves to next or previous newsgroup if at end."
 551   (interactive "p")
 552   (let ((no (+ arg news-current-message-number)))
 553     (if (or (< no news-current-group-begin)
 554             (> no news-current-group-end))
 555         (cond ((= arg 1)
 556                (news-set-current-group-certification)
 557                (news-next-group))
 558               ((= arg -1)
 559                (news-previous-group))
 560               (t (error "Article out of range")))
 561       (let ((plist (news-get-motion-lists
 562                      news-current-message-number
 563                      news-list-of-files)))
 564         (if (< arg 0)
 565             (news-select-message (nth (1- (- arg)) (car (cdr plist))))
 566           (news-select-message (nth (1- arg) (car plist))))))))
 567
 568 (defun news-previous-message (arg)
 569   "Move ARG messages backward in current newsgroup.
 570 With no arg or arg of 1, move one message
 571 and move to previous newsgroup if at beginning.
 572 A negative ARG means move forward."
 573   (interactive "p")
 574   (news-next-message (- arg)))
 575
 576 (defun news-move-to-group (arg)
 577   "Given arg move forward or backward to a new newsgroup."
 578   (let ((cg news-current-news-group))
 579     (let ((plist (news-get-motion-lists cg news-user-group-list))
 580           ngrp)
 581       (if (< arg 0)
 582           (or (setq ngrp (nth (1- (- arg)) (news-cadr plist)))
 583               (error "No previous news groups"))
 584         (or (setq ngrp (nth arg (car plist)))
 585             (error "No more news groups")))
 586       (news-select-news-group ngrp))))
 587
 588 (defun news-next-group ()
 589   "Moves to the next user group."
 590   (interactive)
 591 ;  (message "Moving to next group...")
 592   (news-move-to-group 0)
 593   (while (null news-list-of-files)
 594     (news-move-to-group 0)))
 595 ;  (message "Moving to next group... done.")
 596
 597 (defun news-previous-group ()
 598   "Moves to the previous user group."
 599   (interactive)
 600 ;  (message "Moving to previous group...")
 601   (news-move-to-group -1)
 602   (while (null news-list-of-files)
 603     (news-move-to-group -1)))
 604 ;  (message "Moving to previous group... done.")
 605
 606 (defun news-get-motion-lists (arg listy)
 607   "Given a msgnumber/group this will return a list of two lists;
 608 one for moving forward and one for moving backward."
 609   (let ((temp listy)
 610         (result ()))
 611     (catch 'out
 612       (while temp
 613         (if (equal (car temp) arg)
 614             (throw 'out (cons (cdr temp) (list result)))
 615           (setq result (nconc (list (car temp)) result))
 616           (setq temp (cdr temp)))))))
 617
 618 ;; miscellaneous io routines
 619 (defun news-read-in-file (filename)
 620   (erase-buffer)
 621   (let ((start (point)))
 622   (insert-file-contents filename)
 623   (news-convert-format)
 624   ;; Run each hook that applies to the current newsgroup.
 625   (let ((hooks news-group-hook-alist))
 626     (while hooks
 627       (goto-char start)
 628       (if (string-match (car (car hooks)) news-group-name)
 629           (funcall (cdr (car hooks))))
 630       (setq hooks (cdr hooks))))
 631   (goto-char start)
 632   (forward-line 1)
 633   (if (eobp)
 634       (message "(Empty file?)")
 635     (goto-char start))))
 636
 637 (defun news-convert-format ()
 638   (save-excursion
 639     (save-restriction
 640       (let* ((start (point))
 641              (end (condition-case ()
 642                       (progn (search-forward "\n\n") (point))
 643                     (error nil)))
 644              has-from has-date)
 645        (cond (end
 646               (narrow-to-region start end)
 647               (goto-char start)
 648               (setq has-from (search-forward "\nFrom:" nil t))
 649               (cond ((and (not has-from) has-date)
 650                      (goto-char start)
 651                      (search-forward "\nDate:")
 652                      (beginning-of-line)
 653                      (kill-line) (kill-line)))
 654               (news-delete-headers start)
 655               (goto-char start)))))))
 656
 657 (defun news-show-all-headers ()
 658   "Redisplay current news item with all original headers"
 659   (interactive)
 660   (let (news-ignored-headers
 661         (buffer-read-only ()))
 662     (erase-buffer)
 663     (news-set-mode-line)
 664     (news-read-in-file
 665      (concat news-path
 666              (string-subst-char ?/ ?. news-current-news-group)
 667              "/" (int-to-string news-current-message-number)))))
 668
 669 (defun news-delete-headers (pos)
 670   (goto-char pos)
 671   (and (stringp news-ignored-headers)
 672        (while (re-search-forward news-ignored-headers nil t)
 673          (beginning-of-line)
 674          (delete-region (point)
 675                         (progn (re-search-forward "\n[^ \t]")
 676                                (forward-char -1)
 677                                (point))))))
 678
 679 (defun news-exit ()
 680   "Quit news reading session and update the .newsrc file."
 681   (interactive)
 682   (if (y-or-n-p "Do you really wanna quit reading news ? ")
 683       (progn (message "Updating %s..." news-startup-file)
 684              (news-update-newsrc-file)
 685              (news-write-certifications)
 686              (message "Updating %s... done" news-startup-file)
 687              (message "Now do some real work")
 688              (quit-window)
 689              (switch-to-buffer news-buffer-save)
 690              (setq news-user-group-list ()))
 691     (message "")))
 692
 693 (defun news-update-newsrc-file ()
 694   "Updates the .newsrc file in the users home dir."
 695   (let ((newsrcbuf (find-file-noselect
 696                      (substitute-in-file-name news-startup-file)))
 697         (tem news-user-group-list)
 698         group)
 699     (save-excursion
 700       (if (not (null news-current-news-group))
 701           (news-update-message-read news-current-news-group
 702                                     (news-cdar news-point-pdl)))
 703       (set-buffer newsrcbuf)
 704       (while tem
 705         (setq group (assoc (car tem) news-group-article-assoc))
 706         (if (= (news-cadr (news-cadr group)) (news-caddr (news-cadr group)))
 707             nil
 708           (goto-char 0)
 709           (if (search-forward (concat (car group) ": ") nil t)
 710               (kill-line nil)
 711             (insert (car group) ": \n") (backward-char 1))
 712           (insert (int-to-string (car (news-cadr group))) "-"
 713                   (int-to-string (news-cadr (news-cadr group)))))
 714         (setq tem (cdr tem)))
 715      (while news-unsubscribe-groups
 716        (setq group (assoc (car news-unsubscribe-groups)
 717                           news-group-article-assoc))
 718        (goto-char 0)
 719        (if (search-forward (concat (car group) ": ") nil t)
 720            (progn
 721               (backward-char 2)
 722               (kill-line nil)
 723               (insert "! " (int-to-string (car (news-cadr group)))
 724                       "-" (int-to-string (news-cadr (news-cadr group))))))
 725        (setq news-unsubscribe-groups (cdr news-unsubscribe-groups)))
 726      (save-buffer)
 727      (kill-buffer (current-buffer)))))
 728
 729
 730 (defun news-unsubscribe-group (group)
 731   "Removes you from newgroup GROUP."
 732   (interactive (list (completing-read  "Unsubscribe from group: "
 733                                       news-group-article-assoc)))
 734   (news-unsubscribe-internal group))
 735
 736 (defun news-unsubscribe-current-group ()
 737   "Removes you from the newsgroup you are now reading."
 738   (interactive)
 739   (if (y-or-n-p "Do you really want to unsubscribe from this group ? ")
 740       (news-unsubscribe-internal news-current-news-group)))
 741
 742 (defun news-unsubscribe-internal (group)
 743   (let ((tem (assoc group news-group-article-assoc)))
 744     (if tem
 745         (progn
 746           (setq news-unsubscribe-groups (cons group news-unsubscribe-groups))
 747           (news-update-message-read group (news-cdar news-point-pdl))
 748           (if (equal group news-current-news-group)
 749               (news-next-group))
 750           (message ""))
 751       (error "Not subscribed to group: %s" group))))
 752
 753 (defun news-save-item-in-file (file)
 754   "Save the current article that is being read by appending to a file."
 755   (interactive "FSave item in file: ")
 756   (append-to-file (point-min) (point-max) file))
 757
 758 (defun news-get-pruned-list-of-files (gp-list end-file-no)
 759   "Given a news group it finds all files in the news group.
 760 The arg must be in slashified format.
 761 Using ls was found to be too slow in a previous version."
 762   (let
 763       ((answer
 764         (and
 765          (not (and end-file-no
 766                    (equal (news-set-current-certifiable)
 767                      (news-group-certification gp-list))
 768                    (setq news-list-of-files nil
 769                          news-list-of-files-possibly-bogus t)))
 770          (let* ((file-directory (concat news-path
 771                                         (string-subst-char ?/ ?. gp-list)))
 772                 tem
 773                 (last-winner
 774                  (and end-file-no
 775                       (news-wins file-directory end-file-no)
 776                       (news-find-first-or-last file-directory end-file-no 1))))
 777            (setq news-list-of-files-possibly-bogus t news-list-of-files nil)
 778            (if last-winner
 779                (progn
 780                  (setq news-list-of-files-possibly-bogus t
 781                        news-current-group-end last-winner)
 782                  (while (> last-winner end-file-no)
 783                    (news-push last-winner news-list-of-files)
 784                    (setq last-winner (1- last-winner)))
 785                  news-list-of-files)
 786              (if (or (not (file-directory-p file-directory))
 787                      (not (file-readable-p file-directory)))
 788                  nil
 789                (setq news-list-of-files
 790                      (condition-case error
 791                          (directory-files file-directory)
 792                        (file-error
 793                         (if (string= (nth 2 error) "permission denied")
 794                             (message "Newsgroup %s is read-protected"
 795                                      gp-list)
 796                           (signal 'file-error (cdr error)))
 797                         nil)))
 798                (setq tem news-list-of-files)
 799                (while tem
 800                  (if (or (not (string-match "^[0-9]*$" (car tem)))
 801                          ;; don't get confused by directories that look like numbers
 802                          (file-directory-p
 803                           (concat file-directory "/" (car tem)))
 804                          (<= (string-to-int (car tem)) end-file-no))
 805                      (setq news-list-of-files
 806                            (delq (car tem) news-list-of-files)))
 807                  (setq tem (cdr tem)))
 808                (if (null news-list-of-files)
 809                    (progn (setq news-current-group-end 0)
 810                           nil)
 811                  (setq news-list-of-files
 812                        (mapcar 'string-to-int news-list-of-files))
 813                  (setq news-list-of-files (sort news-list-of-files '<))
 814                  (setq news-current-group-end
 815                        (elt news-list-of-files
 816                             (1- (length news-list-of-files))))
 817                  news-list-of-files)))))))
 818     (or answer (progn (news-set-current-group-certification) nil))))
 819
 820 (defun news-read-files-into-buffer (group reversep)
 821   (let* ((files-start-end (news-cadr (assoc group news-group-article-assoc)))
 822          (start-file-no (car files-start-end))
 823          (end-file-no (news-cadr files-start-end))
 824          (buffer-read-only nil))
 825     (setq news-current-news-group group)
 826     (setq news-current-message-number nil)
 827     (setq news-current-group-end nil)
 828     (news-set-mode-line)
 829     (news-get-pruned-list-of-files group end-file-no)
 830     (news-set-mode-line)
 831     ;; @@ should be a lot smarter than this if we have to move
 832     ;; @@ around correctly.
 833     (setq news-point-pdl (list (cons (car files-start-end)
 834                                      (news-cadr files-start-end))))
 835     (if (null news-list-of-files)
 836         (progn (erase-buffer)
 837                (setq news-current-group-end end-file-no)
 838                (setq news-current-group-begin end-file-no)
 839                (setq news-current-message-number end-file-no)
 840                (news-set-mode-line)
 841 ;              (message "No new articles in " group " group.")
 842                nil)
 843       (setq news-current-group-begin (car news-list-of-files))
 844       (if reversep
 845           (setq news-current-message-number news-current-group-end)
 846         (if (> (car news-list-of-files) end-file-no)
 847             (setcdr (car news-point-pdl) (car news-list-of-files)))
 848         (setq news-current-message-number news-current-group-begin))
 849       (news-set-message-counters)
 850       (news-set-mode-line)
 851       (news-read-in-file (concat news-path
 852                                  (string-subst-char ?/ ?. group)
 853                                  "/"
 854                                  (int-to-string
 855                                    news-current-message-number)))
 856       (news-set-message-counters)
 857       (news-set-mode-line)
 858       t)))
 859
 860 (defun news-add-news-group (gp)
 861   "Resubscribe to or add a USENET news group named GROUP (a string)."
 862 ; @@ (completing-read ...)
 863 ; @@ could be based on news library file ../active (slightly fascist)
 864 ; @@ or (expensive to compute) all directories under the news spool directory
 865   (interactive "sAdd news group: ")
 866   (let ((file-dir (concat news-path (string-subst-char ?/ ?. gp))))
 867     (save-excursion
 868       (if (null (assoc gp news-group-article-assoc))
 869           (let ((newsrcbuf (find-file-noselect
 870                             (substitute-in-file-name news-startup-file))))
 871             (if (file-directory-p file-dir)
 872                 (progn
 873                   (switch-to-buffer newsrcbuf)
 874                   (goto-char 0)
 875                   (if (search-forward (concat gp "! ") nil t)
 876                       (progn
 877                         (message "Re-subscribing to group %s." gp)
 878                         ;;@@ news-unsubscribe-groups isn't being used
 879                         ;;(setq news-unsubscribe-groups
 880                         ;;    (delq gp news-unsubscribe-groups))
 881                         (backward-char 2)
 882                         (delete-char 1)
 883                         (insert ":"))
 884                     (progn
 885                       (message
 886                        "Added %s to your list of newsgroups." gp)
 887                       (end-of-buffer)
 888                       (insert gp ": 1-1\n")))
 889                   (search-backward gp nil t)
 890                   (let (start end endofline tem)
 891                     (search-forward ": " nil t)
 892                     (setq end (point))
 893                     (beginning-of-line)
 894                     (setq start (point))
 895                     (end-of-line)
 896                     (setq endofline (point))
 897                     (setq tem (buffer-substring start (- end 2)))
 898                     (let ((range (news-parse-range
 899                                   (buffer-substring end endofline))))
 900                       (setq news-group-article-assoc
 901                             (cons (list tem (list (car range)
 902                                                   (cdr range)
 903                                                   (cdr range)))
 904                                   news-group-article-assoc))))
 905                   (save-buffer)
 906                   (kill-buffer (current-buffer)))
 907               (message "Newsgroup %s doesn't exist." gp)))
 908         (message "Already subscribed to group %s." gp)))))
 909
 910 (defun news-make-link-to-message (number newname)
 911         "Forges a link to an rnews message numbered number (current if no arg)
 912 Good for hanging on to a message that might or might not be
 913 automatically deleted."
 914   (interactive "P
 915 FName to link to message: ")
 916   (add-name-to-file
 917    (concat news-path
 918            (string-subst-char ?/ ?. news-current-news-group)
 919            "/" (if number
 920                    (prefix-numeric-value number)
 921                  news-current-message-number))
 922    newname))
 923
 924 ;;; caesar-region written by phr@gnu.org  Nov 86
 925 ;;; modified by tower@gnu.org Nov 86
 926 (defun caesar-region (&optional n)
 927   "Caesar rotation of region by N, default 13, for decrypting netnews."
 928   (interactive (if current-prefix-arg   ; Was there a prefix arg?
 929                    (list (prefix-numeric-value current-prefix-arg))
 930                  (list nil)))
 931   (cond ((not (numberp n)) (setq n 13))
 932         (t (setq n (mod n 26))))        ;canonicalize N
 933   (if (not (zerop n))           ; no action needed for a rot of 0
 934       (progn
 935         (if (or (not (boundp 'caesar-translate-table))
 936                 (/= (aref caesar-translate-table ?a) (+ ?a n)))
 937             (let ((i 0) (lower "abcdefghijklmnopqrstuvwxyz") upper)
 938               (message "Building caesar-translate-table...")
 939               (setq caesar-translate-table (make-vector 256 0))
 940               (while (< i 256)
 941                 (aset caesar-translate-table i i)
 942                 (setq i (1+ i)))
 943               (setq lower (concat lower lower) upper (upcase lower) i 0)
 944               (while (< i 26)
 945                 (aset caesar-translate-table (+ ?a i) (aref lower (+ i n)))
 946                 (aset caesar-translate-table (+ ?A i) (aref upper (+ i n)))
 947                 (setq i (1+ i)))
 948               (message "Building caesar-translate-table... done")))
 949         (let ((from (region-beginning))
 950               (to (region-end))
 951               (i 0) str len)
 952           (setq str (buffer-substring from to))
 953           (setq len (length str))
 954           (while (< i len)
 955             (aset str i (aref caesar-translate-table (aref str i)))
 956             (setq i (1+ i)))
 957           (goto-char from)
 958           (kill-region from to)
 959           (insert str)))))
 960
 961 ;;; news-caesar-buffer-body written by paul@media-lab.mit.edu  Wed Oct 1, 1986
 962 ;;; hacked further by tower@gnu.org
 963 (defun news-caesar-buffer-body (&optional rotnum)
 964   "Caesar rotates all letters in the current buffer by 13 places.
 965 Used to encode/decode possibly offensive messages (commonly in net.jokes).
 966 With prefix arg, specifies the number of places to rotate each letter forward.
 967 Mail and USENET news headers are not rotated."
 968   (interactive (if current-prefix-arg   ; Was there a prefix arg?
 969                    (list (prefix-numeric-value current-prefix-arg))
 970                  (list nil)))
 971   (save-excursion
 972     (let ((buffer-status buffer-read-only))
 973       (setq buffer-read-only nil)
 974       ;; setup the region
 975       (set-mark (if (equal major-mode 'news-mode)
 976                     (progn (goto-char (point-min))
 977                            (search-forward "\n\n" nil t))
 978                   (mail-text-start)))
 979       (goto-char (point-max))
 980       (caesar-region rotnum)
 981       (setq buffer-read-only buffer-status))))
 982
 983 (provide 'rnews)
 984
 985 ;;; rnews.el ends here