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@prep.ai.mit.edu 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@prep.ai.mit.edu 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@prep Sep  3 1986
  45 ;; added news-rotate-buffer-body
  46 ;;      tower@prep 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@prep Oct 29 1986
  50 ;; added caesar-region, rename news-caesar-buffer-body, hacked accordingly
  51 ;;      tower@prep Nov 21 1986
  52 ;; added tower@prep 22 Apr 87
  53
  54 ;;; Code:
  55
  56 (require 'mail-utils)
  57
  58 (autoload 'rmail-output "rmailout"
  59   "Append this message to Unix mail file named FILE-NAME."
  60   t)
  61
  62 (autoload 'news-reply "rnewspost"
  63   "Compose and post a reply to the current article on USENET.
  64 While composing the reply, use \\[mail-yank-original] to yank the original
  65 message into it."
  66   t)
  67
  68 (autoload 'news-mail-other-window "rnewspost"
  69   "Send mail in another window.
  70 While composing the message, use \\[mail-yank-original] to yank the
  71 original message into it."
  72   t)
  73
  74 (autoload 'news-post-news "rnewspost"
  75   "Begin editing a new USENET news article to be posted."
  76   t)
  77
  78 (autoload 'news-mail-reply "rnewspost"
  79   "Mail a reply to the author of the current article.
  80 While composing the reply, use \\[mail-yank-original] to yank the original
  81 message into it."
  82   t)
  83
  84 (defvar news-group-hook-alist nil
  85   "Alist of (GROUP-REGEXP . HOOK) pairs.
  86 Just before displaying a message, each HOOK is called
  87 if its GROUP-REGEXP matches the current newsgroup name.")
  88
  89 (defvar rmail-last-file (expand-file-name "~/mbox.news"))
  90
  91 ;Now in paths.el.
  92 ;(defvar news-path "/usr/spool/news/"
  93 ;  "The root directory below which all news files are stored.")
  94
  95 (defvar news-startup-file "$HOME/.newsrc" "Contains ~/.newsrc")
  96 (defvar news-certification-file "$HOME/.news-dates" "Contains ~/.news-dates")
  97
  98 ;; random headers that we decide to ignore.
  99 (defvar news-ignored-headers
 100   "^Path:\\|^Posting-Version:\\|^Article-I.D.:\\|^Expires:\\|^Date-Received:\\|^References:\\|^Control:\\|^Xref:\\|^Lines:\\|^Posted:\\|^Relay-Version:\\|^Message-ID:\\|^Nf-ID:\\|^Nf-From:\\|^Approved:\\|^Sender:"
 101   "All random fields within the header of a message.")
 102
 103 (defvar news-mode-map nil)
 104 (defvar news-read-first-time-p t)
 105 ;; Contains the (dotified) news groups of which you are a member.
 106 (defvar news-user-group-list nil)
 107
 108 (defvar news-current-news-group nil)
 109 (defvar news-current-group-begin nil)
 110 (defvar news-current-group-end  nil)
 111 (defvar news-current-certifications nil
 112         "An assoc list of a group name and the time at which it is
 113 known that the group had no new traffic")
 114 (defvar news-current-certifiable nil
 115         "The time when the directory we are now working on was written")
 116
 117 (defvar news-message-filter nil
 118   "User specifiable filter function that will be called during
 119 formatting of the news file")
 120
 121 ;(defvar news-mode-group-string "Starting-Up"
 122 ;  "Mode line group name info is held in this variable")
 123 (defvar news-list-of-files nil
 124   "Global variable in which we store the list of files
 125 associated with the current newsgroup")
 126 (defvar news-list-of-files-possibly-bogus nil
 127   "variable indicating we only are guessing at which files are available.
 128 Not currently used.")
 129
 130 ;; association list in which we store lists of the form
 131 ;; (pointified-group-name (first last old-last))
 132 (defvar news-group-article-assoc nil)
 133
 134 (defvar news-current-message-number 0 "Displayed Article Number")
 135 (defvar news-total-current-group 0 "Total no of messages in group")
 136
 137 (defvar news-unsubscribe-groups ())
 138 (defvar news-point-pdl () "List of visited news messages.")
 139 (defvar news-no-jumps-p t)
 140 (defvar news-buffer () "Buffer into which news files are read.")
 141
 142 (defmacro news-push (item ref)
 143   (list 'setq ref (list 'cons item ref)))
 144
 145 (defmacro news-cadr (x) (list 'car (list 'cdr x)))
 146 (defmacro news-cdar (x) (list 'cdr (list 'car x)))
 147 (defmacro news-caddr (x) (list 'car (list 'cdr (list 'cdr x))))
 148 (defmacro news-cadar (x) (list 'car (list 'cdr (list 'car x))))
 149 (defmacro news-caadr (x) (list 'car (list 'car (list 'cdr x))))
 150 (defmacro news-cdadr (x) (list 'cdr (list 'car (list 'cdr x))))
 151
 152 (defmacro news-wins (pfx index)
 153   (` (file-exists-p (concat (, pfx) "/" (int-to-string (, index))))))
 154
 155 (defvar news-max-plausible-gap 2
 156         "* In an rnews directory, the maximum possible gap size.
 157 A gap is a sequence of missing messages between two messages that exist.
 158 An empty file does not contribute to a gap -- it ends one.")
 159
 160 (defun news-find-first-and-last (prefix base)
 161   (and (news-wins prefix base)
 162        (cons (news-find-first-or-last prefix base -1)
 163              (news-find-first-or-last prefix base 1))))
 164
 165 (defmacro news-/ (a1 a2)
 166 ;; a form of / that guarantees that (/ -1 2) = 0
 167   (if (zerop (/ -1 2))
 168       (` (/ (, a1) (, a2)))
 169     (` (if (< (, a1) 0)
 170            (- (/ (- (, a1)) (, a2)))
 171          (/ (, a1) (, a2))))))
 172
 173 (defun news-find-first-or-last (pfx base dirn)
 174   ;; first use powers of two to find a plausible ceiling
 175   (let ((original-dir dirn))
 176     (while (news-wins pfx (+ base dirn))
 177       (setq dirn (* dirn 2)))
 178     (setq dirn (news-/ dirn 2))
 179     ;; Then use a binary search to find the high water mark
 180     (let ((offset (news-/ dirn 2)))
 181       (while (/= offset 0)
 182         (if (news-wins pfx (+ base dirn offset))
 183             (setq dirn (+ dirn offset)))
 184         (setq offset (news-/ offset 2))))
 185     ;; If this high-water mark is bogus, recurse.
 186     (let ((offset (* news-max-plausible-gap original-dir)))
 187       (while (and (/= offset 0) (not (news-wins pfx (+ base dirn offset))))
 188         (setq offset (- offset original-dir)))
 189       (if (= offset 0)
 190           (+ base dirn)
 191         (news-find-first-or-last pfx (+ base dirn offset) original-dir)))))
 192
 193 (defun rnews ()
 194 "Read USENET news for groups for which you are a member and add or
 195 delete groups.
 196 You can reply to articles posted and send articles to any group.
 197
 198 Type \\[describe-mode] once reading news to get a list of rnews commands."
 199   (interactive)
 200   (let ((last-buffer (buffer-name)))
 201     (make-local-variable 'rmail-last-file)
 202     (switch-to-buffer (setq news-buffer (get-buffer-create "*news*")))
 203     (news-mode)
 204     (setq news-buffer-save last-buffer)
 205     (setq buffer-read-only nil)
 206     (erase-buffer)
 207     (setq buffer-read-only t)
 208     (set-buffer-modified-p t)
 209     (sit-for 0)
 210     (message "Getting new USENET news...")
 211     (news-set-mode-line)
 212     (news-get-certifications)
 213     (news-get-new-news)))
 214
 215 (defun news-group-certification (group)
 216   (cdr-safe (assoc group news-current-certifications)))
 217
 218
 219 (defun news-set-current-certifiable ()
 220   ;; Record the date that corresponds to the directory you are about to check
 221   (let ((file (concat news-path
 222                       (string-subst-char ?/ ?. news-current-news-group))))
 223     (setq news-current-certifiable
 224           (nth 5 (file-attributes
 225                   (or (file-symlink-p file) file))))))
 226
 227 (defun news-get-certifications ()
 228   ;; Read the certified-read file from last session
 229   (save-excursion
 230     (save-window-excursion
 231       (setq news-current-certifications
 232             (car-safe
 233              (condition-case var
 234                  (let*
 235                      ((file (substitute-in-file-name news-certification-file))
 236                       (buf (find-file-noselect file)))
 237                    (and (file-exists-p file)
 238                         (progn
 239                           (switch-to-buffer buf 'norecord)
 240                           (unwind-protect
 241                               (read-from-string (buffer-string))
 242                             (kill-buffer buf)))))
 243                (error nil)))))))
 244
 245 (defun news-write-certifications ()
 246   ;; Write a certification file.
 247   ;; This is an assoc list of group names with doubletons that represent
 248   ;; mod times of the directory when group is read completely.
 249   (save-excursion
 250     (save-window-excursion
 251       (with-output-to-temp-buffer
 252           "*CeRtIfIcAtIoNs*"
 253           (print news-current-certifications))
 254       (let ((buf (get-buffer "*CeRtIfIcAtIoNs*")))
 255         (switch-to-buffer buf)
 256         (write-file (substitute-in-file-name news-certification-file))
 257         (kill-buffer buf)))))
 258
 259 (defun news-set-current-group-certification ()
 260   (let ((cgc (assoc news-current-news-group news-current-certifications)))
 261     (if cgc (setcdr cgc news-current-certifiable)
 262       (news-push (cons news-current-news-group news-current-certifiable)
 263                  news-current-certifications))))
 264
 265 (defun news-set-minor-modes ()
 266   "Creates a minor mode list that has group name, total articles,
 267 and attribute for current article."
 268   (setq news-minor-modes (list (cons 'foo
 269                                      (concat news-current-message-number
 270                                              "/"
 271                                              news-total-current-group
 272                                              (news-get-attribute-string)))))
 273   ;; Detect Emacs versions 18.16 and up, which display
 274   ;; directly from news-minor-modes by using a list for mode-name.
 275   (or (boundp 'minor-mode-alist)
 276       (setq minor-modes news-minor-modes)))
 277
 278 (defun news-set-message-counters ()
 279   "Scan through current news-groups filelist to figure out how many messages
 280 are there. Set counters for use with minor mode display."
 281     (if (null news-list-of-files)
 282         (setq news-current-message-number 0)))
 283
 284 (if news-mode-map
 285     nil
 286   (setq news-mode-map (make-keymap))
 287   (suppress-keymap news-mode-map)
 288   (define-key news-mode-map "." 'beginning-of-buffer)
 289   (define-key news-mode-map " " 'scroll-up)
 290   (define-key news-mode-map "\177" 'scroll-down)
 291   (define-key news-mode-map "n" 'news-next-message)
 292   (define-key news-mode-map "c" 'news-make-link-to-message)
 293   (define-key news-mode-map "p" 'news-previous-message)
 294   (define-key news-mode-map "j" 'news-goto-message)
 295   (define-key news-mode-map "q" 'news-exit)
 296   (define-key news-mode-map "e" 'news-exit)
 297   (define-key news-mode-map "\ej" 'news-goto-news-group)
 298   (define-key news-mode-map "\en" 'news-next-group)
 299   (define-key news-mode-map "\ep" 'news-previous-group)
 300   (define-key news-mode-map "l" 'news-list-news-groups)
 301   (define-key news-mode-map "?" 'describe-mode)
 302   (define-key news-mode-map "g" 'news-get-new-news)
 303   (define-key news-mode-map "f" 'news-reply)
 304   (define-key news-mode-map "m" 'news-mail-other-window)
 305   (define-key news-mode-map "a" 'news-post-news)
 306   (define-key news-mode-map "r" 'news-mail-reply)
 307   (define-key news-mode-map "o" 'news-save-item-in-file)
 308   (define-key news-mode-map "\C-o" 'rmail-output)
 309   (define-key news-mode-map "t" 'news-show-all-headers)
 310   (define-key news-mode-map "x" 'news-force-update)
 311   (define-key news-mode-map "A" 'news-add-news-group)
 312   (define-key news-mode-map "u" 'news-unsubscribe-current-group)
 313   (define-key news-mode-map "U" 'news-unsubscribe-group)
 314   (define-key news-mode-map "\C-c\C-r" 'news-caesar-buffer-body))
 315
 316 (defun news-mode ()
 317   "News Mode is used by M-x rnews for reading USENET Newsgroups articles.
 318 New readers can find additional help in newsgroup: news.announce.newusers .
 319 All normal editing commands are turned off.
 320 Instead, these commands are available:
 321
 322 .       move point to front of this news article (same as Meta-<).
 323 Space   scroll to next screen of this news article.
 324 Delete  scroll down previous page of this news article.
 325 n       move to next news article, possibly next group.
 326 p       move to previous news article, possibly previous group.
 327 j       jump to news article specified by numeric position.
 328 M-j     jump to news group.
 329 M-n     goto next news group.
 330 M-p     goto previous news group.
 331 l       list all the news groups with current status.
 332 ?       print this help message.
 333 C-c C-r caesar rotate all letters by 13 places in the article's body (rot13).
 334 g       get new USENET news.
 335 f       post a reply article to USENET.
 336 a       post an original news article.
 337 A       add a newsgroup.
 338 o       save the current article in the named file (append if file exists).
 339 C-o     output this message to a Unix-format mail file (append it).
 340 c       \"copy\" (actually link) current or prefix-arg msg to file.
 341         warning: target directory and message file must be on same device
 342                 (UNIX magic)
 343 t       show all the headers this news article originally had.
 344 q       quit reading news after updating .newsrc file.
 345 e       exit updating .newsrc file.
 346 m       mail a news article.  Same as C-x 4 m.
 347 x       update last message seen to be the current message.
 348 r       mail a reply to this news article.  Like m but initializes some fields.
 349 u       unsubscribe from current newsgroup.
 350 U       unsubscribe from specified newsgroup."
 351   (interactive)
 352   (kill-all-local-variables)
 353   (make-local-variable 'news-read-first-time-p)
 354   (setq news-read-first-time-p t)
 355   (make-local-variable 'news-current-news-group)
 356 ;  (setq news-current-news-group "??")
 357   (make-local-variable 'news-current-group-begin)
 358   (setq news-current-group-begin 0)
 359   (make-local-variable 'news-current-message-number)
 360   (setq news-current-message-number 0)
 361   (make-local-variable 'news-total-current-group)
 362   (make-local-variable 'news-buffer-save)
 363   (make-local-variable 'version-control)
 364   (setq version-control 'never)
 365   (make-local-variable 'news-point-pdl)
 366 ;  This breaks it.  I don't have time to figure out why. -- RMS
 367 ;  (make-local-variable 'news-group-article-assoc)
 368   (setq major-mode 'news-mode)
 369   (setq mode-line-process '(news-minor-modes))
 370   (setq mode-name "NEWS")
 371   (news-set-mode-line)
 372   (set-syntax-table text-mode-syntax-table)
 373   (use-local-map news-mode-map)
 374   (setq local-abbrev-table text-mode-abbrev-table)
 375   (run-hooks 'news-mode-hook))
 376
 377 (defun string-subst-char (new old string)
 378   (let (index)
 379     (setq old (regexp-quote (char-to-string old))
 380           string (substring string 0))
 381     (while (setq index (string-match old string))
 382       (aset string index new)))
 383   string)
 384
 385 ;; update read message number
 386 (defmacro news-update-message-read (ngroup nno)
 387   (list 'setcar
 388         (list 'news-cdadr
 389               (list 'assoc ngroup 'news-group-article-assoc))
 390         nno))
 391
 392 (defun news-parse-range (number-string)
 393   "Parse string representing range of numbers of he form <a>-<b>
 394 to a list (a . b)"
 395   (let ((n (string-match "-" number-string)))
 396     (if n
 397         (cons (string-to-int (substring number-string 0 n))
 398               (string-to-int (substring number-string (1+ n))))
 399       (setq n (string-to-int number-string))
 400       (cons n n))))
 401
 402 ;(defun is-in (elt lis)
 403 ;  (catch 'foo
 404 ;    (while lis
 405 ;      (if (equal (car lis) elt)
 406 ;         (throw 'foo t)
 407 ;       (setq lis (cdr lis))))))
 408
 409 (defun news-get-new-news ()
 410   "Get new USENET news, if there is any for the current user."
 411   (interactive)
 412   (if (not (null news-user-group-list))
 413       (news-update-newsrc-file))
 414   (setq news-group-article-assoc ())
 415   (setq news-user-group-list ())
 416   (message "Looking up %s file..." news-startup-file)
 417   (let ((file (substitute-in-file-name news-startup-file))
 418         (temp-user-groups ()))
 419     (save-excursion
 420       (let ((newsrcbuf (find-file-noselect file))
 421             start end endofline tem)
 422         (set-buffer newsrcbuf)
 423         (goto-char 0)
 424         (while (search-forward ": " nil t)
 425           (setq end (point))
 426           (beginning-of-line)
 427           (setq start (point))
 428           (end-of-line)
 429           (setq endofline (point))
 430           (setq tem (buffer-substring start (- end 2)))
 431           (let ((range (news-parse-range
 432                         (buffer-substring end endofline))))
 433             (if (assoc tem news-group-article-assoc)
 434                 (message "You are subscribed twice to %s; I ignore second"
 435                          tem)
 436               (setq temp-user-groups (cons tem temp-user-groups)
 437                     news-group-article-assoc
 438                     (cons (list tem (list (car range)
 439                                           (cdr range)
 440                                           (cdr range)))
 441                           news-group-article-assoc)))))
 442         (kill-buffer newsrcbuf)))
 443     (setq temp-user-groups (nreverse temp-user-groups))
 444     (message "Prefrobnicating...")
 445     (switch-to-buffer news-buffer)
 446     (setq news-user-group-list temp-user-groups)
 447     (while (and temp-user-groups
 448                 (not (news-read-files-into-buffer
 449                       (car temp-user-groups) nil)))
 450       (setq temp-user-groups (cdr temp-user-groups)))
 451     (if (null temp-user-groups)
 452         (message "No news is good news.")
 453       (message ""))))
 454
 455 (defun news-list-news-groups ()
 456   "Display all the news groups to which you belong."
 457   (interactive)
 458   (with-output-to-temp-buffer "*Newsgroups*"
 459     (save-excursion
 460       (set-buffer standard-output)
 461       (insert
 462         "News Group        Msg No.       News Group        Msg No.\n")
 463       (insert
 464         "-------------------------       -------------------------\n")
 465       (let ((temp news-user-group-list)
 466             (flag nil))
 467         (while temp
 468           (let ((item (assoc (car temp) news-group-article-assoc)))
 469             (insert (car item))
 470             (indent-to (if flag 52 20))
 471             (insert (int-to-string (news-cadr (news-cadr item))))
 472             (if flag
 473                 (insert "\n")
 474               (indent-to 33))
 475             (setq temp (cdr temp) flag (not flag))))))))
 476
 477 ;; Mode line hack
 478 (defun news-set-mode-line ()
 479   "Set mode line string to something useful."
 480   (setq mode-line-process
 481         (concat " "
 482                 (if (integerp news-current-message-number)
 483                     (int-to-string news-current-message-number)
 484                  "??")
 485                 "/"
 486                 (if (integerp news-current-group-end)
 487                     (int-to-string news-current-group-end)
 488                   news-current-group-end)))
 489   (setq mode-line-buffer-identification
 490         (concat "NEWS: "
 491                 news-current-news-group
 492                 ;; Enough spaces to pad group name to 17 positions.
 493                 (substring "                 "
 494                            0 (max 0 (- 17 (length news-current-news-group))))))
 495   (set-buffer-modified-p t)
 496   (sit-for 0))
 497
 498 (defun news-goto-news-group (gp)
 499   "Takes a string and goes to that news group."
 500   (interactive (list (completing-read "NewsGroup: "
 501                                       news-group-article-assoc)))
 502   (message "Jumping to news group %s..." gp)
 503   (news-select-news-group gp)
 504   (message "Jumping to news group %s... done." gp))
 505
 506 (defun news-select-news-group (gp)
 507   (let ((grp (assoc gp news-group-article-assoc)))
 508     (if (null grp)
 509         (error "Group %s not subscribed to" gp)
 510       (progn
 511         (news-update-message-read news-current-news-group
 512                                   (news-cdar news-point-pdl))
 513         (news-read-files-into-buffer  (car grp) nil)
 514         (news-set-mode-line)))))
 515
 516 (defun news-goto-message (arg)
 517   "Goes to the article ARG in current newsgroup."
 518   (interactive "p")
 519   (if (null current-prefix-arg)
 520       (setq arg (read-no-blanks-input "Go to article: " "")))
 521   (news-select-message arg))
 522
 523 (defun news-select-message (arg)
 524   (if (stringp arg) (setq arg (string-to-int arg)))
 525   (let ((file (concat news-path
 526                       (string-subst-char ?/ ?. news-current-news-group)
 527                       "/" arg)))
 528     (if (= arg
 529            (or (news-cadr (memq (news-cdar news-point-pdl) news-list-of-files))
 530                0))
 531         (setcdr (car news-point-pdl) arg))
 532     (setq news-current-message-number arg)
 533     (if (file-exists-p file)
 534         (let ((buffer-read-only nil))
 535           (news-read-in-file file)
 536           (news-set-mode-line))
 537       (news-set-mode-line)
 538       (error "Article %d nonexistent" arg))))
 539
 540 (defun news-force-update ()
 541   "updates the position of last article read in the current news group"
 542   (interactive)
 543   (setcdr (car news-point-pdl) news-current-message-number)
 544   (message "Updated to %d" news-current-message-number))
 545
 546 (defun news-next-message (arg)
 547   "Move ARG messages forward within one newsgroup.
 548 Negative ARG moves backward.
 549 If ARG is 1 or -1, moves to next or previous newsgroup if at end."
 550   (interactive "p")
 551   (let ((no (+ arg news-current-message-number)))
 552     (if (or (< no news-current-group-begin)
 553             (> no news-current-group-end))
 554         (cond ((= arg 1)
 555                (news-set-current-group-certification)
 556                (news-next-group))
 557               ((= arg -1)
 558                (news-previous-group))
 559               (t (error "Article out of range")))
 560       (let ((plist (news-get-motion-lists
 561                      news-current-message-number
 562                      news-list-of-files)))
 563         (if (< arg 0)
 564             (news-select-message (nth (1- (- arg)) (car (cdr plist))))
 565           (news-select-message (nth (1- arg) (car plist))))))))
 566
 567 (defun news-previous-message (arg)
 568   "Move ARG messages backward in current newsgroup.
 569 With no arg or arg of 1, move one message
 570 and move to previous newsgroup if at beginning.
 571 A negative ARG means move forward."
 572   (interactive "p")
 573   (news-next-message (- arg)))
 574
 575 (defun news-move-to-group (arg)
 576   "Given arg move forward or backward to a new newsgroup."
 577   (let ((cg news-current-news-group))
 578     (let ((plist (news-get-motion-lists cg news-user-group-list))
 579           ngrp)
 580       (if (< arg 0)
 581           (or (setq ngrp (nth (1- (- arg)) (news-cadr plist)))
 582               (error "No previous news groups"))
 583         (or (setq ngrp (nth arg (car plist)))
 584             (error "No more news groups")))
 585       (news-select-news-group ngrp))))
 586
 587 (defun news-next-group ()
 588   "Moves to the next user group."
 589   (interactive)
 590 ;  (message "Moving to next group...")
 591   (news-move-to-group 0)
 592   (while (null news-list-of-files)
 593     (news-move-to-group 0)))
 594 ;  (message "Moving to next group... done.")
 595
 596 (defun news-previous-group ()
 597   "Moves to the previous user group."
 598   (interactive)
 599 ;  (message "Moving to previous group...")
 600   (news-move-to-group -1)
 601   (while (null news-list-of-files)
 602     (news-move-to-group -1)))
 603 ;  (message "Moving to previous group... done.")
 604
 605 (defun news-get-motion-lists (arg listy)
 606   "Given a msgnumber/group this will return a list of two lists;
 607 one for moving forward and one for moving backward."
 608   (let ((temp listy)
 609         (result ()))
 610     (catch 'out
 611       (while temp
 612         (if (equal (car temp) arg)
 613             (throw 'out (cons (cdr temp) (list result)))
 614           (setq result (nconc (list (car temp)) result))
 615           (setq temp (cdr temp)))))))
 616
 617 ;; miscellaneous io routines
 618 (defun news-read-in-file (filename)
 619   (erase-buffer)
 620   (let ((start (point)))
 621   (insert-file-contents filename)
 622   (news-convert-format)
 623   ;; Run each hook that applies to the current newsgroup.
 624   (let ((hooks news-group-hook-alist))
 625     (while hooks
 626       (goto-char start)
 627       (if (string-match (car (car hooks)) news-group-name)
 628           (funcall (cdr (car hooks))))
 629       (setq hooks (cdr hooks))))
 630   (goto-char start)
 631   (forward-line 1)
 632   (if (eobp)
 633       (message "(Empty file?)")
 634     (goto-char start))))
 635
 636 (defun news-convert-format ()
 637   (save-excursion
 638     (save-restriction
 639       (let* ((start (point))
 640              (end (condition-case ()
 641                       (progn (search-forward "\n\n") (point))
 642                     (error nil)))
 643              has-from has-date)
 644        (cond (end
 645               (narrow-to-region start end)
 646               (goto-char start)
 647               (setq has-from (search-forward "\nFrom:" nil t))
 648               (cond ((and (not has-from) has-date)
 649                      (goto-char start)
 650                      (search-forward "\nDate:")
 651                      (beginning-of-line)
 652                      (kill-line) (kill-line)))
 653               (news-delete-headers start)
 654               (goto-char start)))))))
 655
 656 (defun news-show-all-headers ()
 657   "Redisplay current news item with all original headers"
 658   (interactive)
 659   (let (news-ignored-headers
 660         (buffer-read-only ()))
 661     (erase-buffer)
 662     (news-set-mode-line)
 663     (news-read-in-file
 664      (concat news-path
 665              (string-subst-char ?/ ?. news-current-news-group)
 666              "/" (int-to-string news-current-message-number)))))
 667
 668 (defun news-delete-headers (pos)
 669   (goto-char pos)
 670   (and (stringp news-ignored-headers)
 671        (while (re-search-forward news-ignored-headers nil t)
 672          (beginning-of-line)
 673          (delete-region (point)
 674                         (progn (re-search-forward "\n[^ \t]")
 675                                (forward-char -1)
 676                                (point))))))
 677
 678 (defun news-exit ()
 679   "Quit news reading session and update the .newsrc file."
 680   (interactive)
 681   (if (y-or-n-p "Do you really wanna quit reading news ? ")
 682       (progn (message "Updating %s..." news-startup-file)
 683              (news-update-newsrc-file)
 684              (news-write-certifications)
 685              (message "Updating %s... done" news-startup-file)
 686              (message "Now do some real work")
 687              (and (fboundp 'bury-buffer) (bury-buffer (current-buffer)))
 688              (switch-to-buffer news-buffer-save)
 689              (setq news-user-group-list ()))
 690     (message "")))
 691
 692 (defun news-update-newsrc-file ()
 693   "Updates the .newsrc file in the users home dir."
 694   (let ((newsrcbuf (find-file-noselect
 695                      (substitute-in-file-name news-startup-file)))
 696         (tem news-user-group-list)
 697         group)
 698     (save-excursion
 699       (if (not (null news-current-news-group))
 700           (news-update-message-read news-current-news-group
 701                                     (news-cdar news-point-pdl)))
 702       (set-buffer newsrcbuf)
 703       (while tem
 704         (setq group (assoc (car tem) news-group-article-assoc))
 705         (if (= (news-cadr (news-cadr group)) (news-caddr (news-cadr group)))
 706             nil
 707           (goto-char 0)
 708           (if (search-forward (concat (car group) ": ") nil t)
 709               (kill-line nil)
 710             (insert (car group) ": \n") (backward-char 1))
 711           (insert (int-to-string (car (news-cadr group))) "-"
 712                   (int-to-string (news-cadr (news-cadr group)))))
 713         (setq tem (cdr tem)))
 714      (while news-unsubscribe-groups
 715        (setq group (assoc (car news-unsubscribe-groups)
 716                           news-group-article-assoc))
 717        (goto-char 0)
 718        (if (search-forward (concat (car group) ": ") nil t)
 719            (progn
 720               (backward-char 2)
 721               (kill-line nil)
 722               (insert "! " (int-to-string (car (news-cadr group)))
 723                       "-" (int-to-string (news-cadr (news-cadr group))))))
 724        (setq news-unsubscribe-groups (cdr news-unsubscribe-groups)))
 725      (save-buffer)
 726      (kill-buffer (current-buffer)))))
 727
 728
 729 (defun news-unsubscribe-group (group)
 730   "Removes you from newgroup GROUP."
 731   (interactive (list (completing-read  "Unsubscribe from group: "
 732                                       news-group-article-assoc)))
 733   (news-unsubscribe-internal group))
 734
 735 (defun news-unsubscribe-current-group ()
 736   "Removes you from the newsgroup you are now reading."
 737   (interactive)
 738   (if (y-or-n-p "Do you really want to unsubscribe from this group ? ")
 739       (news-unsubscribe-internal news-current-news-group)))
 740
 741 (defun news-unsubscribe-internal (group)
 742   (let ((tem (assoc group news-group-article-assoc)))
 743     (if tem
 744         (progn
 745           (setq news-unsubscribe-groups (cons group news-unsubscribe-groups))
 746           (news-update-message-read group (news-cdar news-point-pdl))
 747           (if (equal group news-current-news-group)
 748               (news-next-group))
 749           (message ""))
 750       (error "Not subscribed to group: %s" group))))
 751
 752 (defun news-save-item-in-file (file)
 753   "Save the current article that is being read by appending to a file."
 754   (interactive "FSave item in file: ")
 755   (append-to-file (point-min) (point-max) file))
 756
 757 (defun news-get-pruned-list-of-files (gp-list end-file-no)
 758   "Given a news group it finds all files in the news group.
 759 The arg must be in slashified format.
 760 Using ls was found to be too slow in a previous version."
 761   (let
 762       ((answer
 763         (and
 764          (not (and end-file-no
 765                    (equal (news-set-current-certifiable)
 766                      (news-group-certification gp-list))
 767                    (setq news-list-of-files nil
 768                          news-list-of-files-possibly-bogus t)))
 769          (let* ((file-directory (concat news-path
 770                                         (string-subst-char ?/ ?. gp-list)))
 771                 tem
 772                 (last-winner
 773                  (and end-file-no
 774                       (news-wins file-directory end-file-no)
 775                       (news-find-first-or-last file-directory end-file-no 1))))
 776            (setq news-list-of-files-possibly-bogus t news-list-of-files nil)
 777            (if last-winner
 778                (progn
 779                  (setq news-list-of-files-possibly-bogus t
 780                        news-current-group-end last-winner)
 781                  (while (> last-winner end-file-no)
 782                    (news-push last-winner news-list-of-files)
 783                    (setq last-winner (1- last-winner)))
 784                  news-list-of-files)
 785              (if (or (not (file-directory-p file-directory))
 786                      (not (file-readable-p file-directory)))
 787                  nil
 788                (setq news-list-of-files
 789                      (condition-case error
 790                          (directory-files file-directory)
 791                        (file-error
 792                         (if (string= (nth 2 error) "permission denied")
 793                             (message "Newsgroup %s is read-protected"
 794                                      gp-list)
 795                           (signal 'file-error (cdr error)))
 796                         nil)))
 797                (setq tem news-list-of-files)
 798                (while tem
 799                  (if (or (not (string-match "^[0-9]*$" (car tem)))
 800                          ;; don't get confused by directories that look like numbers
 801                          (file-directory-p
 802                           (concat file-directory "/" (car tem)))
 803                          (<= (string-to-int (car tem)) end-file-no))
 804                      (setq news-list-of-files
 805                            (delq (car tem) news-list-of-files)))
 806                  (setq tem (cdr tem)))
 807                (if (null news-list-of-files)
 808                    (progn (setq news-current-group-end 0)
 809                           nil)
 810                  (setq news-list-of-files
 811                        (mapcar 'string-to-int news-list-of-files))
 812                  (setq news-list-of-files (sort news-list-of-files '<))
 813                  (setq news-current-group-end
 814                        (elt news-list-of-files
 815                             (1- (length news-list-of-files))))
 816                  news-list-of-files)))))))
 817     (or answer (progn (news-set-current-group-certification) nil))))
 818
 819 (defun news-read-files-into-buffer (group reversep)
 820   (let* ((files-start-end (news-cadr (assoc group news-group-article-assoc)))
 821          (start-file-no (car files-start-end))
 822          (end-file-no (news-cadr files-start-end))
 823          (buffer-read-only nil))
 824     (setq news-current-news-group group)
 825     (setq news-current-message-number nil)
 826     (setq news-current-group-end nil)
 827     (news-set-mode-line)
 828     (news-get-pruned-list-of-files group end-file-no)
 829     (news-set-mode-line)
 830     ;; @@ should be a lot smarter than this if we have to move
 831     ;; @@ around correctly.
 832     (setq news-point-pdl (list (cons (car files-start-end)
 833                                      (news-cadr files-start-end))))
 834     (if (null news-list-of-files)
 835         (progn (erase-buffer)
 836                (setq news-current-group-end end-file-no)
 837                (setq news-current-group-begin end-file-no)
 838                (setq news-current-message-number end-file-no)
 839                (news-set-mode-line)
 840 ;              (message "No new articles in " group " group.")
 841                nil)
 842       (setq news-current-group-begin (car news-list-of-files))
 843       (if reversep
 844           (setq news-current-message-number news-current-group-end)
 845         (if (> (car news-list-of-files) end-file-no)
 846             (setcdr (car news-point-pdl) (car news-list-of-files)))
 847         (setq news-current-message-number news-current-group-begin))
 848       (news-set-message-counters)
 849       (news-set-mode-line)
 850       (news-read-in-file (concat news-path
 851                                  (string-subst-char ?/ ?. group)
 852                                  "/"
 853                                  (int-to-string
 854                                    news-current-message-number)))
 855       (news-set-message-counters)
 856       (news-set-mode-line)
 857       t)))
 858
 859 (defun news-add-news-group (gp)
 860   "Resubscribe to or add a USENET news group named GROUP (a string)."
 861 ; @@ (completing-read ...)
 862 ; @@ could be based on news library file ../active (slightly fascist)
 863 ; @@ or (expensive to compute) all directories under the news spool directory
 864   (interactive "sAdd news group: ")
 865   (let ((file-dir (concat news-path (string-subst-char ?/ ?. gp))))
 866     (save-excursion
 867       (if (null (assoc gp news-group-article-assoc))
 868           (let ((newsrcbuf (find-file-noselect
 869                             (substitute-in-file-name news-startup-file))))
 870             (if (file-directory-p file-dir)
 871                 (progn
 872                   (switch-to-buffer newsrcbuf)
 873                   (goto-char 0)
 874                   (if (search-forward (concat gp "! ") nil t)
 875                       (progn
 876                         (message "Re-subscribing to group %s." gp)
 877                         ;;@@ news-unsubscribe-groups isn't being used
 878                         ;;(setq news-unsubscribe-groups
 879                         ;;    (delq gp news-unsubscribe-groups))
 880                         (backward-char 2)
 881                         (delete-char 1)
 882                         (insert ":"))
 883                     (progn
 884                       (message
 885                        "Added %s to your list of newsgroups." gp)
 886                       (end-of-buffer)
 887                       (insert gp ": 1-1\n")))
 888                   (search-backward gp nil t)
 889                   (let (start end endofline tem)
 890                     (search-forward ": " nil t)
 891                     (setq end (point))
 892                     (beginning-of-line)
 893                     (setq start (point))
 894                     (end-of-line)
 895                     (setq endofline (point))
 896                     (setq tem (buffer-substring start (- end 2)))
 897                     (let ((range (news-parse-range
 898                                   (buffer-substring end endofline))))
 899                       (setq news-group-article-assoc
 900                             (cons (list tem (list (car range)
 901                                                   (cdr range)
 902                                                   (cdr range)))
 903                                   news-group-article-assoc))))
 904                   (save-buffer)
 905                   (kill-buffer (current-buffer)))
 906               (message "Newsgroup %s doesn't exist." gp)))
 907         (message "Already subscribed to group %s." gp)))))
 908
 909 (defun news-make-link-to-message (number newname)
 910         "Forges a link to an rnews message numbered number (current if no arg)
 911 Good for hanging on to a message that might or might not be
 912 automatically deleted."
 913   (interactive "P
 914 FName to link to message: ")
 915   (add-name-to-file
 916    (concat news-path
 917            (string-subst-char ?/ ?. news-current-news-group)
 918            "/" (if number
 919                    (prefix-numeric-value number)
 920                  news-current-message-number))
 921    newname))
 922
 923 ;;; caesar-region written by phr@prep.ai.mit.edu  Nov 86
 924 ;;; modified by tower@prep Nov 86
 925 (defun caesar-region (&optional n)
 926   "Caesar rotation of region by N, default 13, for decrypting netnews."
 927   (interactive (if current-prefix-arg   ; Was there a prefix arg?
 928                    (list (prefix-numeric-value current-prefix-arg))
 929                  (list nil)))
 930   (cond ((not (numberp n)) (setq n 13))
 931         (t (setq n (mod n 26))))        ;canonicalize N
 932   (if (not (zerop n))           ; no action needed for a rot of 0
 933       (progn
 934         (if (or (not (boundp 'caesar-translate-table))
 935                 (/= (aref caesar-translate-table ?a) (+ ?a n)))
 936             (let ((i 0) (lower "abcdefghijklmnopqrstuvwxyz") upper)
 937               (message "Building caesar-translate-table...")
 938               (setq caesar-translate-table (make-vector 256 0))
 939               (while (< i 256)
 940                 (aset caesar-translate-table i i)
 941                 (setq i (1+ i)))
 942               (setq lower (concat lower lower) upper (upcase lower) i 0)
 943               (while (< i 26)
 944                 (aset caesar-translate-table (+ ?a i) (aref lower (+ i n)))
 945                 (aset caesar-translate-table (+ ?A i) (aref upper (+ i n)))
 946                 (setq i (1+ i)))
 947               (message "Building caesar-translate-table... done")))
 948         (let ((from (region-beginning))
 949               (to (region-end))
 950               (i 0) str len)
 951           (setq str (buffer-substring from to))
 952           (setq len (length str))
 953           (while (< i len)
 954             (aset str i (aref caesar-translate-table (aref str i)))
 955             (setq i (1+ i)))
 956           (goto-char from)
 957           (kill-region from to)
 958           (insert str)))))
 959
 960 ;;; news-caesar-buffer-body written by paul@media-lab.mit.edu  Wed Oct 1, 1986
 961 ;;; hacked further by tower@prep.ai.mit.edu
 962 (defun news-caesar-buffer-body (&optional rotnum)
 963   "Caesar rotates all letters in the current buffer by 13 places.
 964 Used to encode/decode possibly offensive messages (commonly in net.jokes).
 965 With prefix arg, specifies the number of places to rotate each letter forward.
 966 Mail and USENET news headers are not rotated."
 967   (interactive (if current-prefix-arg   ; Was there a prefix arg?
 968                    (list (prefix-numeric-value current-prefix-arg))
 969                  (list nil)))
 970   (save-excursion
 971     (let ((buffer-status buffer-read-only))
 972       (setq buffer-read-only nil)
 973       ;; setup the region
 974       (set-mark (if (progn (goto-char (point-min))
 975                             (search-forward
 976                              (concat "\n"
 977                                      (if (equal major-mode 'news-mode)
 978                                          ""
 979                                        mail-header-separator)
 980                                      "\n") nil t))
 981                      (point)
 982                    (point-min)))
 983       (goto-char (point-max))
 984       (caesar-region rotnum)
 985       (setq buffer-read-only buffer-status))))
 986
 987 (provide 'rnews)
 988
 989 ;;; rnews.el ends here