lisp/nntp.el

   1 ;;; nntp.el --- nntp access for Gnus
   2
   3 ;; Copyright (C) 1987,88,89,90,92,93,94,95,96 Free Software Foundation, Inc.
   4
   5 ;; Author: Masanobu UMEDA <umerin@flab.flab.fujitsu.junet>
   6 ;;      Lars Magne Ingebrigtsen <larsi@ifi.uio.no>
   7 ;; Keywords: news
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation; either version 2, or (at your option)
  14 ;; any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  24 ;; Boston, MA 02111-1307, USA.
  25
  26 ;;; Commentary:
  27
  28 ;;; Code:
  29
  30 (require 'rnews)
  31 (require 'sendmail)
  32 (require 'nnheader)
  33
  34 (eval-when-compile (require 'cl))
  35
  36 (eval-and-compile
  37   (autoload 'news-setup "rnewspost")
  38   (autoload 'news-reply-mode "rnewspost")
  39   (autoload 'nnmail-request-post-buffer "nnmail")
  40   (autoload 'cancel-timer "timer")
  41   (autoload 'telnet "telnet" nil t)
  42   (autoload 'telnet-send-input "telnet" nil t)
  43   (autoload 'timezone-parse-date "timezone"))
  44
  45 (defvar nntp-server-hook nil
  46   "*Hooks for the NNTP server.
  47 If the kanji code of the NNTP server is different from the local kanji
  48 code, the correct kanji code of the buffer associated with the NNTP
  49 server must be specified as follows:
  50
  51 \(setq nntp-server-hook
  52       (function
  53        (lambda ()
  54          ;; Server's Kanji code is EUC (NEmacs hack).
  55          (make-local-variable 'kanji-fileio-code)
  56          (setq kanji-fileio-code 0))))
  57
  58 If you'd like to change something depending on the server in this
  59 hook, use the variable `nntp-address'.")
  60
  61 (defvar nntp-server-opened-hook nil
  62   "*Hook used for sending commands to the server at startup.
  63 The default value is `nntp-send-mode-reader', which makes an innd
  64 server spawn an nnrpd server.  Another useful function to put in this
  65 hook might be `nntp-send-authinfo', which will prompt for a password
  66 to allow posting from the server.  Note that this is only necessary to
  67 do on servers that use strict access control.")
  68 (add-hook 'nntp-server-opened-hook 'nntp-send-mode-reader)
  69
  70 (defvar nntp-open-server-function 'nntp-open-network-stream
  71   "*Function used for connecting to a remote system.
  72 It will be called with the address of the remote system.
  73
  74 Two pre-made functions are `nntp-open-network-stream', which is the
  75 default, and simply connects to some port or other on the remote
  76 system (see nntp-port-number).  The other is `nntp-open-rlogin', which
  77 does an rlogin on the remote system, and then does a telnet to the
  78 NNTP server available there (see nntp-rlogin-parameters).")
  79
  80 (defvar nntp-rlogin-parameters '("telnet" "${NNTPSERVER:=localhost}" "nntp")
  81   "*Parameters to `nntp-open-login'.
  82 That function may be used as `nntp-open-server-function'.  In that
  83 case, this list will be used as the parameter list given to rsh.")
  84
  85 (defvar nntp-rlogin-user-name nil
  86   "*User name on remote system when using the rlogin connect method.")
  87
  88 (defvar nntp-address nil
  89   "*The name of the NNTP server.")
  90
  91 (defvar nntp-port-number "nntp"
  92   "*Port number to connect to.")
  93
  94 (defvar nntp-large-newsgroup 50
  95   "*The number of the articles which indicates a large newsgroup.
  96 If the number of the articles is greater than the value, verbose
  97 messages will be shown to indicate the current status.")
  98
  99 (defvar nntp-buggy-select (memq system-type '(fujitsu-uts))
 100   "*t if your select routine is buggy.
 101 If the select routine signals error or fall into infinite loop while
 102 waiting for the server response, the variable must be set to t.  In
 103 case of Fujitsu UTS, it is set to T since `accept-process-output'
 104 doesn't work properly.")
 105
 106 (defvar nntp-maximum-request 400
 107   "*The maximum number of the requests sent to the NNTP server at one time.
 108 If Emacs hangs up while retrieving headers, set the variable to a
 109 lower value.")
 110
 111 (defvar nntp-debug-read 10000
 112   "*Display '...' every 10Kbytes of a message being received if it is non-nil.
 113 If it is a number, dots are displayed per the number.")
 114
 115 (defvar nntp-nov-is-evil nil
 116   "*If non-nil, nntp will never attempt to use XOVER when talking to the server.")
 117
 118 (defvar nntp-xover-commands '("XOVER" "XOVERVIEW")
 119   "*List of strings that are used as commands to fetch NOV lines from a server.
 120 The strings are tried in turn until a positive response is gotten. If
 121 none of the commands are successful, nntp will just grab headers one
 122 by one.")
 123
 124 (defvar nntp-nov-gap 20
 125   "*Maximum allowed gap between two articles.
 126 If the gap between two consecutive articles is bigger than this
 127 variable, split the XOVER request into two requests.")
 128
 129 (defvar nntp-connection-timeout nil
 130   "*Number of seconds to wait before an nntp connection times out.
 131 If this variable is nil, which is the default, no timers are set.")
 132
 133 (defvar nntp-news-default-headers nil
 134   "*If non-nil, override `mail-default-headers' when posting news.")
 135
 136 (defvar nntp-prepare-server-hook nil
 137   "*Hook run before a server is opened.
 138 If can be used to set up a server remotely, for instance.  Say you
 139 have an account at the machine \"other.machine\".  This machine has
 140 access to an NNTP server that you can't access locally.  You could
 141 then use this hook to rsh to the remote machine and start a proxy NNTP
 142 server there that you can connect to.")
 143
 144 (defvar nntp-async-number 5
 145   "*How many articles should be prefetched when in asynchronous mode.")
 146
 147
 148 \f
 149
 150 (defconst nntp-version "nntp 4.0"
 151   "Version numbers of this version of NNTP.")
 152
 153 (defvar nntp-server-buffer nil
 154   "Buffer associated with the NNTP server process.")
 155
 156 (defvar nntp-server-process nil
 157   "The NNTP server process.
 158 You'd better not use this variable in NNTP front-end program, but
 159 instead use `nntp-server-buffer'.")
 160
 161 (defvar nntp-status-string nil
 162   "Save the server response message.
 163 You'd better not use this variable in NNTP front-end program but
 164 instead call function `nntp-status-message' to get status message.")
 165
 166 (defvar nntp-opened-connections nil
 167   "All (possibly) opened connections.")
 168
 169 (defvar nntp-server-xover 'try)
 170 (defvar nntp-server-list-active-group 'try)
 171 (defvar nntp-current-group "")
 172 (defvar nntp-timeout-servers nil)
 173
 174 (defvar nntp-async-process nil)
 175 (defvar nntp-async-buffer nil)
 176 (defvar nntp-async-articles nil)
 177 (defvar nntp-async-fetched nil)
 178 (defvar nntp-async-group-alist nil)
 179
 180
 181 \f
 182 (defvar nntp-current-server nil)
 183 (defvar nntp-server-alist nil)
 184 (defvar nntp-server-variables
 185   (list
 186    (list 'nntp-server-hook nntp-server-hook)
 187    (list 'nntp-server-opened-hook nntp-server-opened-hook)
 188    (list 'nntp-port-number nntp-port-number)
 189    (list 'nntp-address nntp-address)
 190    (list 'nntp-large-newsgroup nntp-large-newsgroup)
 191    (list 'nntp-buggy-select nntp-buggy-select)
 192    (list 'nntp-maximum-request nntp-maximum-request)
 193    (list 'nntp-debug-read nntp-debug-read)
 194    (list 'nntp-nov-is-evil nntp-nov-is-evil)
 195    (list 'nntp-xover-commands nntp-xover-commands)
 196    (list 'nntp-connection-timeout nntp-connection-timeout)
 197    (list 'nntp-news-default-headers nntp-news-default-headers)
 198    (list 'nntp-prepare-server-hook nntp-prepare-server-hook)
 199    (list 'nntp-async-number nntp-async-number)
 200    '(nntp-async-process nil)
 201    '(nntp-async-buffer nil)
 202    '(nntp-async-articles nil)
 203    '(nntp-async-fetched nil)
 204    '(nntp-async-group-alist nil)
 205    '(nntp-server-process nil)
 206    '(nntp-status-string nil)
 207    '(nntp-server-xover try)
 208    '(nntp-server-list-active-group try)
 209    '(nntp-current-group "")))
 210
 211 \f
 212 ;;; Interface functions.
 213
 214 (defun nntp-retrieve-headers (sequence &optional newsgroup server)
 215   "Retrieve the headers to the articles in SEQUENCE."
 216   (nntp-possibly-change-server newsgroup server)
 217   (save-excursion
 218     (set-buffer nntp-server-buffer)
 219     (erase-buffer)
 220     (if (and (not gnus-nov-is-evil)
 221              (not nntp-nov-is-evil)
 222              (nntp-retrieve-headers-with-xover sequence))
 223         'nov
 224       (let ((number (length sequence))
 225             (count 0)
 226             (received 0)
 227             (last-point (point-min)))
 228         ;; Send HEAD command.
 229         (while sequence
 230           (nntp-send-strings-to-server
 231            "HEAD" (if (numberp (car sequence)) (int-to-string (car sequence))
 232                     (car sequence)))
 233           (setq sequence (cdr sequence)
 234                 count (1+ count))
 235           ;; Every 400 header requests we have to read stream in order
 236           ;;  to avoid deadlock.
 237           (if (or (null sequence)       ;All requests have been sent.
 238                   (zerop (% count nntp-maximum-request)))
 239               (progn
 240                 (nntp-accept-response)
 241                 (while (progn
 242                          (goto-char last-point)
 243                          ;; Count replies.
 244                          (while (re-search-forward "^[0-9]" nil t)
 245                            (setq received (1+ received)))
 246                          (setq last-point (point))
 247                          (< received count))
 248                   ;; If number of headers is greater than 100, give
 249                   ;;  informative messages.
 250                   (and (numberp nntp-large-newsgroup)
 251                        (> number nntp-large-newsgroup)
 252                        (zerop (% received 20))
 253                        (message "NNTP: Receiving headers... %d%%"
 254                                 (/ (* received 100) number)))
 255                   (nntp-accept-response)))))
 256         ;; Wait for text of last command.
 257         (goto-char (point-max))
 258         (re-search-backward "^[0-9]" nil t)
 259         (if (looking-at "^[23]")
 260             (while (progn
 261                      (goto-char (- (point-max) 3))
 262                      (not (looking-at "^\\.\r?\n")))
 263               (nntp-accept-response)))
 264         (and (numberp nntp-large-newsgroup)
 265              (> number nntp-large-newsgroup)
 266              (message "NNTP: Receiving headers...done"))
 267
 268         ;; Now all of replies are received.
 269         (setq received number)
 270         ;; First, fold continuation lines.
 271         (goto-char (point-min))
 272         (while (re-search-forward "\\(\r?\n[ \t]+\\)+" nil t)
 273           (replace-match " "))
 274         ;; Remove all "\r"'s
 275         (goto-char (point-min))
 276         (while (search-forward "\r" nil t)
 277           (replace-match ""))
 278         'headers))))
 279
 280
 281 (defun nntp-retrieve-groups (groups &optional server)
 282   (nntp-possibly-change-server nil server)
 283   (save-excursion
 284     (set-buffer nntp-server-buffer)
 285     (and (eq nntp-server-list-active-group 'try)
 286          (nntp-try-list-active (car groups)))
 287     (erase-buffer)
 288     (let ((count 0)
 289           (received 0)
 290           (last-point (point-min))
 291           (command (if nntp-server-list-active-group
 292                        "LIST ACTIVE" "GROUP")))
 293       (while groups
 294         (nntp-send-strings-to-server command (car groups))
 295         (setq groups (cdr groups))
 296         (setq count (1+ count))
 297         ;; Every 400 requests we have to read the stream in
 298         ;; order to avoid deadlocks.
 299         (if (or (null groups)           ;All requests have been sent.
 300                 (zerop (% count nntp-maximum-request)))
 301             (progn
 302               (nntp-accept-response)
 303               (while (progn
 304                        (goto-char last-point)
 305                        ;; Count replies.
 306                        (while (re-search-forward "^[0-9]" nil t)
 307                          (setq received (1+ received)))
 308                        (setq last-point (point))
 309                        (< received count))
 310                 (nntp-accept-response)))))
 311
 312       ;; Wait for the reply from the final command.
 313       (if nntp-server-list-active-group
 314           (progn
 315             (goto-char (point-max))
 316             (re-search-backward "^[0-9]" nil t)
 317             (if (looking-at "^[23]")
 318                 (while (progn
 319                          (goto-char (- (point-max) 3))
 320                          (not (looking-at "^\\.\r?\n")))
 321                   (nntp-accept-response)))))
 322
 323       ;; Now all replies are received. We remove CRs.
 324       (goto-char (point-min))
 325       (while (search-forward "\r" nil t)
 326         (replace-match "" t t))
 327
 328       (if nntp-server-list-active-group
 329           (progn
 330             ;; We have read active entries, so we just delete the
 331             ;; superfluous gunk.
 332             (goto-char (point-min))
 333             (while (re-search-forward "^[.2-5]" nil t)
 334               (delete-region (match-beginning 0)
 335                              (progn (forward-line 1) (point))))
 336             'active)
 337         'group))))
 338
 339 (defun nntp-open-server (server &optional defs connectionless)
 340   "Open the virtual server SERVER.
 341 If CONNECTIONLESS is non-nil, don't attempt to connect to any physical
 342 servers."
 343   (nnheader-init-server-buffer)
 344   (if (nntp-server-opened server)
 345       t
 346     (if (or (stringp (car defs))
 347             (numberp (car defs)))
 348         (setq defs (cons (list 'nntp-port-number (car defs)) (cdr defs))))
 349     (or (assq 'nntp-address defs)
 350         (setq defs (append defs (list (list 'nntp-address server)))))
 351     (if (and nntp-current-server
 352              (not (equal server nntp-current-server)))
 353         (setq nntp-server-alist
 354               (cons (list nntp-current-server
 355                           (nnheader-save-variables nntp-server-variables))
 356                     nntp-server-alist)))
 357     (let ((state (assoc server nntp-server-alist)))
 358       (if state
 359           (progn
 360             (nnheader-restore-variables (nth 1 state))
 361             (setq nntp-server-alist (delq state nntp-server-alist)))
 362         (nnheader-set-init-variables nntp-server-variables defs)))
 363     (setq nntp-current-server server)
 364     ;; We have now changed to the proper virtual server.  We then
 365     ;; check that the physical server is opened.
 366     (if (or (nntp-server-opened server)
 367             connectionless)
 368         t
 369       (if (member nntp-address nntp-timeout-servers)
 370           nil
 371         ;; We open a connection to the physical nntp server.
 372         (run-hooks 'nntp-prepare-server-hook)
 373         (nntp-open-server-semi-internal nntp-address nntp-port-number)))))
 374
 375 (defun nntp-close-server (&optional server)
 376   "Close connection to SERVER."
 377   (nntp-possibly-change-server nil server t)
 378   (unwind-protect
 379       (progn
 380         ;; Un-set default sentinel function before closing connection.
 381         (and nntp-server-process
 382              (eq 'nntp-default-sentinel
 383                  (process-sentinel nntp-server-process))
 384              (set-process-sentinel nntp-server-process nil))
 385         ;; We cannot send QUIT command unless the process is running.
 386         (if (nntp-server-opened)
 387             (nntp-send-command nil "QUIT")))
 388     (nntp-close-server-internal server)
 389     (setq nntp-timeout-servers (delete server nntp-timeout-servers))))
 390
 391 (defalias 'nntp-request-quit (symbol-function 'nntp-close-server))
 392
 393 (defun nntp-request-close ()
 394   "Close all server connections."
 395   (let (proc)
 396     (while nntp-opened-connections
 397       (setq proc (pop nntp-opened-connections))
 398       (and proc (delete-process proc)))
 399     (and nntp-async-buffer
 400          (get-buffer nntp-async-buffer)
 401          (kill-buffer nntp-async-buffer))
 402     (while nntp-server-alist
 403       (and (setq proc (nth 1 (assq 'nntp-async-buffer
 404                                    (car nntp-server-alist))))
 405            (buffer-name proc)
 406            (kill-buffer proc))
 407       (setq nntp-server-alist (cdr nntp-server-alist)))
 408     (setq nntp-current-server nil
 409           nntp-timeout-servers nil
 410           nntp-async-group-alist nil)))
 411
 412 (defun nntp-server-opened (&optional server)
 413   "Say whether a connection to SERVER has been opened."
 414   (and (equal server nntp-current-server)
 415        nntp-server-buffer
 416        (buffer-name nntp-server-buffer)
 417        nntp-server-process
 418        (memq (process-status nntp-server-process) '(open run))))
 419
 420 (defun nntp-status-message (&optional server)
 421   "Return server status as a string."
 422   (if (and nntp-status-string
 423            ;; NNN MESSAGE
 424            (string-match "[0-9][0-9][0-9][ \t]+\\([^\r]*\\).*$"
 425                          nntp-status-string))
 426       (substring nntp-status-string (match-beginning 1) (match-end 1))
 427     ;; Empty message if nothing.
 428     (or nntp-status-string "")))
 429
 430 (defun nntp-request-article (id &optional newsgroup server buffer)
 431   "Request article ID (message-id or number)."
 432   (nntp-possibly-change-server newsgroup server)
 433
 434   (let (found)
 435
 436     ;; First we see whether we can get the article from the async buffer.
 437     (if (and (numberp id)
 438              nntp-async-articles
 439              (memq id nntp-async-fetched))
 440         (save-excursion
 441           (set-buffer nntp-async-buffer)
 442           (let ((opoint (point))
 443                 (art (if (numberp id) (int-to-string id) id))
 444                 beg end)
 445             (if (and (or (re-search-forward (concat "^2.. +" art) nil t)
 446                          (progn
 447                            (goto-char (point-min))
 448                            (re-search-forward (concat "^2.. +" art) opoint t)))
 449                      (progn
 450                        (beginning-of-line)
 451                        (setq beg (point)
 452                              end (re-search-forward "^\\.\r?\n" nil t))))
 453                 (progn
 454                   (setq found t)
 455                   (save-excursion
 456                     (set-buffer (or buffer nntp-server-buffer))
 457                     (erase-buffer)
 458                     (insert-buffer-substring nntp-async-buffer beg end)
 459                     (let ((nntp-server-buffer (current-buffer)))
 460                       (nntp-decode-text)))
 461                   (delete-region beg end)
 462                   (and nntp-async-articles
 463                        (nntp-async-fetch-articles id)))))))
 464
 465     (if found
 466         t
 467       ;; The article was not in the async buffer, so we fetch it now.
 468       (unwind-protect
 469           (progn
 470             (if buffer (set-process-buffer nntp-server-process buffer))
 471             (let ((nntp-server-buffer (or buffer nntp-server-buffer))
 472                   (art (or (and (numberp id) (int-to-string id)) id)))
 473               ;; If NEmacs, end of message may look like: "\256\215" (".^M")
 474               (prog1
 475                   (nntp-send-command "^\\.\r?\n" "ARTICLE" art)
 476                 (nntp-decode-text)
 477                 (and nntp-async-articles (nntp-async-fetch-articles id)))))
 478         (if buffer (set-process-buffer
 479                     nntp-server-process nntp-server-buffer))))))
 480
 481 (defun nntp-request-body (id &optional newsgroup server)
 482   "Request body of article ID (message-id or number)."
 483   (nntp-possibly-change-server newsgroup server)
 484   (prog1
 485       ;; If NEmacs, end of message may look like: "\256\215" (".^M")
 486       (nntp-send-command
 487        "^\\.\r?\n" "BODY" (or (and (numberp id) (int-to-string id)) id))
 488     (nntp-decode-text)))
 489
 490 (defun nntp-request-head (id &optional newsgroup server)
 491   "Request head of article ID (message-id or number)."
 492   (nntp-possibly-change-server newsgroup server)
 493   (prog1
 494       (nntp-send-command
 495        "^\\.\r?\n" "HEAD" (or (and (numberp id) (int-to-string id)) id))
 496     (nntp-decode-text)))
 497
 498 (defun nntp-request-stat (id &optional newsgroup server)
 499   "Request STAT of article ID (message-id or number)."
 500   (nntp-possibly-change-server newsgroup server)
 501   (nntp-send-command
 502    "^[23].*\r?\n" "STAT" (or (and (numberp id) (int-to-string id)) id)))
 503
 504 (defun nntp-request-group (group &optional server dont-check)
 505   "Select GROUP."
 506   (nntp-send-command "^.*\r?\n" "GROUP" group)
 507   (setq nntp-current-group group)
 508   (save-excursion
 509     (set-buffer nntp-server-buffer)
 510     (goto-char (point-min))
 511     (looking-at "[23]")))
 512
 513 (defun nntp-request-asynchronous (group &optional server articles)
 514   (and nntp-async-articles (nntp-async-request-group group))
 515   (and
 516    nntp-async-number
 517    (if (not (or (nntp-async-server-opened)
 518                 (nntp-async-open-server)))
 519        (progn
 520          (message "Can't open second connection to %s" nntp-address)
 521          (ding)
 522          (setq nntp-async-articles nil)
 523          (sit-for 2))
 524      (setq nntp-async-articles articles)
 525      (setq nntp-async-fetched nil)
 526      (save-excursion
 527        (set-buffer nntp-async-buffer)
 528        (erase-buffer))
 529      (nntp-async-send-strings "GROUP" group)
 530      t)))
 531
 532 (defun nntp-list-active-group (group &optional server)
 533   (nntp-send-command "^.*\r?\n" "LIST ACTIVE" group))
 534
 535 (defun nntp-request-group-description (group &optional server)
 536   "Get description of GROUP."
 537   (nntp-possibly-change-server nil server)
 538   (prog1
 539       (nntp-send-command "^.*\r?\n" "XGTITLE" group)
 540     (nntp-decode-text)))
 541
 542 (defun nntp-close-group (group &optional server)
 543   (setq nntp-current-group nil)
 544   t)
 545
 546 (defun nntp-request-list (&optional server)
 547   "List active groups."
 548   (nntp-possibly-change-server nil server)
 549   (prog1
 550       (nntp-send-command "^\\.\r?\n" "LIST")
 551     (nntp-decode-text)))
 552
 553 (defun nntp-request-list-newsgroups (&optional server)
 554   "List groups."
 555   (nntp-possibly-change-server nil server)
 556   (prog1
 557       (nntp-send-command "^\\.\r?\n" "LIST NEWSGROUPS")
 558     (nntp-decode-text)))
 559
 560 (defun nntp-request-newgroups (date &optional server)
 561   "List new groups."
 562   (nntp-possibly-change-server nil server)
 563   (let* ((date (timezone-parse-date date))
 564          (time-string
 565           (format "%s%02d%02d %s%s%s"
 566                   (substring (aref date 0) 2) (string-to-int (aref date 1))
 567                   (string-to-int (aref date 2)) (substring (aref date 3) 0 2)
 568                   (substring
 569                    (aref date 3) 3 5) (substring (aref date 3) 6 8))))
 570     (prog1
 571         (nntp-send-command "^\\.\r?\n" "NEWGROUPS" time-string)
 572       (nntp-decode-text))))
 573
 574 (defun nntp-request-list-distributions (&optional server)
 575   "List distributions."
 576   (nntp-possibly-change-server nil server)
 577   (prog1
 578       (nntp-send-command "^\\.\r?\n" "LIST DISTRIBUTIONS")
 579     (nntp-decode-text)))
 580
 581 (defun nntp-request-last (&optional newsgroup server)
 582   "Decrease the current article pointer."
 583   (nntp-possibly-change-server newsgroup server)
 584   (nntp-send-command "^[23].*\r?\n" "LAST"))
 585
 586 (defun nntp-request-next (&optional newsgroup server)
 587   "Advance the current article pointer."
 588   (nntp-possibly-change-server newsgroup server)
 589   (nntp-send-command "^[23].*\r?\n" "NEXT"))
 590
 591 (defun nntp-request-post (&optional server)
 592   "Post the current buffer."
 593   (nntp-possibly-change-server nil server)
 594   (save-excursion
 595     (set-buffer nntp-server-buffer)
 596     (erase-buffer))
 597   (if (nntp-send-command "^[23].*\r?\n" "POST")
 598       (progn
 599         (save-excursion
 600           (set-buffer nntp-server-buffer)
 601           (erase-buffer))
 602         (nntp-encode-text)
 603         (nntp-send-region-to-server (point-min) (point-max))
 604         ;; 1.2a NNTP's post command is buggy. "^M" (\r) is not
 605         ;;  appended to end of the status message.
 606         (nntp-wait-for-response "^[23].*\n"))))
 607
 608 (defun nntp-request-post-buffer
 609   (post group subject header article-buffer info follow-to respect-poster)
 610   "Request a buffer suitable for composing an article.
 611 If POST, this is an original article; otherwise it's a followup.
 612 GROUP is the group to be posted to, the article should have subject
 613 SUBJECT.  HEADER is a Gnus header vector.  ARTICLE-BUFFER contains the
 614 article being followed up.  INFO is a Gnus info list.  If FOLLOW-TO,
 615 post to this group instead.  If RESPECT-POSTER, heed the special
 616 \"poster\" value of the Followup-to header."
 617   (if (assq 'to-address (nth 5 info))
 618       (nnmail-request-post-buffer
 619        post group subject header article-buffer info follow-to respect-poster)
 620     (let ((mail-default-headers
 621            (or nntp-news-default-headers mail-default-headers))
 622           from date to followup-to newsgroups message-of
 623           references distribution message-id)
 624       (save-excursion
 625         (set-buffer (get-buffer-create "*post-news*"))
 626         (news-reply-mode)
 627         (if (and (buffer-modified-p)
 628                  (> (buffer-size) 0)
 629                  (not (y-or-n-p "Unsent article being composed; erase it? ")))
 630             ()
 631           (erase-buffer)
 632           (if post
 633               (news-setup nil subject nil group nil)
 634             (save-excursion
 635               (set-buffer article-buffer)
 636               (goto-char (point-min))
 637               (narrow-to-region (point-min)
 638                                 (progn (search-forward "\n\n") (point)))
 639               (setq from (mail-header-from header))
 640               (setq date (mail-header-date header))
 641               (and from
 642                    (let ((stop-pos
 643                           (string-match "  *at \\|  *@ \\| *(\\| *<" from)))
 644                      (setq
 645                       message-of
 646                       (concat (if stop-pos (substring from 0 stop-pos) from)
 647                               "'s message of " date))))
 648               (setq subject (or subject (mail-header-subject header)))
 649               (or (string-match "^[Rr][Ee]:" subject)
 650                   (setq subject (concat "Re: " subject)))
 651               (setq followup-to (mail-fetch-field "followup-to"))
 652               (if (or (null respect-poster) ;Ignore followup-to: field.
 653                       (string-equal "" followup-to) ;Bogus header.
 654                       (string-equal "poster" followup-to);Poster
 655                       (and (eq respect-poster 'ask)
 656                            followup-to
 657                            (not (y-or-n-p (concat "Followup to "
 658                                                   followup-to "? ")))))
 659                   (setq followup-to nil))
 660               (setq newsgroups
 661                     (or follow-to followup-to (mail-fetch-field "newsgroups")))
 662               (setq references (mail-header-references header))
 663               (setq distribution (mail-fetch-field "distribution"))
 664               ;; Remove bogus distribution.
 665               (and (stringp distribution)
 666                    (string-match "world" distribution)
 667                    (setq distribution nil))
 668               (setq message-id (mail-header-id header))
 669               (widen))
 670             (setq news-reply-yank-from from)
 671             (setq news-reply-yank-message-id message-id)
 672             (news-setup to subject message-of
 673                         (if (stringp newsgroups) newsgroups "")
 674                         article-buffer)
 675             (if (and newsgroups (listp newsgroups))
 676                 (progn
 677                   (goto-char (point-min))
 678                   (while newsgroups
 679                     (insert (car (car newsgroups)) ": "
 680                             (cdr (car newsgroups)) "\n")
 681                     (setq newsgroups (cdr newsgroups)))))
 682             (nnheader-insert-references references message-id)
 683             (if distribution
 684                 (progn
 685                   (mail-position-on-field "Distribution")
 686                   (insert distribution)))))
 687         (current-buffer)))))
 688
 689 ;;; Internal functions.
 690
 691 (defun nntp-send-mode-reader ()
 692   "Send the MODE READER command to the nntp server.
 693 This function is supposed to be called from `nntp-server-opened-hook'.
 694 It will make innd servers spawn an nnrpd process to allow actual article
 695 reading."
 696   (nntp-send-command "^.*\r?\n" "MODE READER"))
 697
 698 (defun nntp-send-authinfo ()
 699   "Send the AUTHINFO to the nntp server.
 700 This function is supposed to be called from `nntp-server-opened-hook'.
 701 It will prompt for a password."
 702   (nntp-send-command "^.*\r?\n" "AUTHINFO USER" (user-login-name))
 703   (nntp-send-command "^.*\r?\n" "AUTHINFO PASS"
 704                      (read-string "NNTP password: ")))
 705
 706 (defun nntp-send-authinfo-from-file ()
 707   "Send the AUTHINFO to the nntp server.
 708 This function is supposed to be called from `nntp-server-opened-hook'.
 709 It will prompt for a password."
 710   (and (file-exists-p "~/.nntp-authinfo")
 711        (save-excursion
 712          (set-buffer (get-buffer-create " *tull*"))
 713          (insert-file-contents "~/.nntp-authinfo")
 714          (goto-char (point-min))
 715          (nntp-send-command "^.*\r?\n" "AUTHINFO USER" (user-login-name))
 716          (nntp-send-command "^.*\r?\n" "AUTHINFO PASS"
 717                             (buffer-substring (point)
 718                                               (progn (end-of-line) (point))))
 719          (kill-buffer (current-buffer)))))
 720
 721 (defun nntp-default-sentinel (proc status)
 722   "Default sentinel function for NNTP server process."
 723   (let ((servers nntp-server-alist)
 724         server)
 725     ;; Go through the alist of server names and find the name of the
 726     ;; server that the process that sent the signal is connected to.
 727     ;; If you get my drift.
 728     (if (equal proc nntp-server-process)
 729         (setq server nntp-address)
 730       (while (and servers
 731                   (not (equal proc (nth 1 (assq 'nntp-server-process
 732                                                 (car servers))))))
 733         (setq servers (cdr servers)))
 734       (setq server (car (car servers))))
 735     (and server
 736          (progn
 737            (message "nntp: Connection closed to server %s" server)
 738            (ding)))))
 739
 740 (defun nntp-kill-connection (server)
 741   (let ((proc (nth 1 (assq 'nntp-server-process
 742                            (assoc server nntp-server-alist)))))
 743     (and proc (delete-process (process-name proc)))
 744     (nntp-close-server server)
 745     (setq nntp-timeout-servers (cons server nntp-timeout-servers))
 746     (setq nntp-status-string
 747           (message "Connection timed out to server %s." server))
 748     (ding)
 749     (sit-for 1)))
 750
 751 ;; Encoding and decoding of NNTP text.
 752
 753 (defun nntp-decode-text ()
 754   "Decode text transmitted by NNTP.
 755 0. Delete status line.
 756 1. Delete `^M' at end of line.
 757 2. Delete `.' at end of buffer (end of text mark).
 758 3. Delete `.' at beginning of line."
 759   (save-excursion
 760     (set-buffer nntp-server-buffer)
 761     ;; Insert newline at end of buffer.
 762     (goto-char (point-max))
 763     (or (bolp) (insert "\n"))
 764     ;; Delete status line.
 765     (goto-char (point-min))
 766     (delete-region (point) (progn (forward-line 1) (point)))
 767     ;; Delete `^M' at the end of lines.
 768     (while (not (eobp))
 769       (end-of-line)
 770       (and (= (preceding-char) ?\r)
 771            (delete-char -1))
 772       (forward-line 1))
 773     ;; Delete `.' at end of the buffer (end of text mark).
 774     (goto-char (point-max))
 775     (forward-line -1)
 776     (if (looking-at "^\\.\n")
 777         (delete-region (point) (progn (forward-line 1) (point))))
 778     ;; Replace `..' at beginning of line with `.'.
 779     (goto-char (point-min))
 780     ;; (replace-regexp "^\\.\\." ".")
 781     (while (search-forward "\n.." nil t)
 782       (delete-char -1))))
 783
 784 (defun nntp-encode-text ()
 785   "Encode text in current buffer for NNTP transmission.
 786 1. Insert `.' at beginning of line.
 787 2. Insert `.' at end of buffer (end of text mark)."
 788   (save-excursion
 789     ;; Insert newline at end of buffer.
 790     (goto-char (point-max))
 791     (or (bolp) (insert "\n"))
 792     ;; Replace `.' at beginning of line with `..'.
 793     (goto-char (point-min))
 794     ;; (replace-regexp "^\\." "..")
 795     (while (search-forward "\n." nil t)
 796       (insert "."))
 797     ;; Insert `.' at end of buffer (end of text mark).
 798     (goto-char (point-max))
 799     (insert ".\r\n")))
 800
 801 \f
 802 ;;;
 803 ;;; Synchronous Communication with NNTP Server.
 804 ;;;
 805
 806 (defun nntp-send-command (response cmd &rest args)
 807   "Wait for server RESPONSE after sending CMD and optional ARGS to server."
 808   (save-excursion
 809     ;; Clear communication buffer.
 810     (set-buffer nntp-server-buffer)
 811     (erase-buffer)
 812     (apply 'nntp-send-strings-to-server cmd args)
 813     (if response
 814         (nntp-wait-for-response response)
 815       t)))
 816
 817 (defun nntp-wait-for-response (regexp &optional slow)
 818   "Wait for server response which matches REGEXP."
 819   (save-excursion
 820     (let ((status t)
 821           (wait t)
 822           (dotnum 0)                    ;Number of "." being displayed.
 823           (dotsize                      ;How often "." displayed.
 824            (if (numberp nntp-debug-read) nntp-debug-read 10000)))
 825       (set-buffer nntp-server-buffer)
 826       ;; Wait for status response (RFC977).
 827       ;; 1xx - Informative message.
 828       ;; 2xx - Command ok.
 829       ;; 3xx - Command ok so far, send the rest of it.
 830       ;; 4xx - Command was correct, but couldn't be performed for some
 831       ;;       reason.
 832       ;; 5xx - Command unimplemented, or incorrect, or a serious
 833       ;;       program error occurred.
 834       (nntp-accept-response)
 835       (while wait
 836         (goto-char (point-min))
 837         (if slow
 838             (progn
 839               (cond ((re-search-forward "^[23][0-9][0-9]" nil t)
 840                      (setq wait nil))
 841                     ((re-search-forward "^[45][0-9][0-9]" nil t)
 842                      (setq status nil)
 843                      (setq wait nil))
 844                     (t (nntp-accept-response)))
 845               (if (not wait) (delete-region (point-min)
 846                                             (progn (beginning-of-line)
 847                                                    (point)))))
 848           (cond ((looking-at "[23]")
 849                  (setq wait nil))
 850                 ((looking-at "[45]")
 851                  (setq status nil)
 852                  (setq wait nil))
 853                 (t (nntp-accept-response)))))
 854       ;; Save status message.
 855       (end-of-line)
 856       (setq nntp-status-string
 857             (buffer-substring (point-min) (point)))
 858       (if status
 859           (progn
 860             (setq wait t)
 861             (while wait
 862               (goto-char (point-max))
 863               (forward-line -1)         ;(beginning-of-line)
 864               ;;(message (buffer-substring
 865               ;;         (point)
 866               ;;         (save-excursion (end-of-line) (point))))
 867               (if (looking-at regexp)
 868                   (setq wait nil)
 869                 (if nntp-debug-read
 870                     (let ((newnum (/ (buffer-size) dotsize)))
 871                       (if (not (= dotnum newnum))
 872                           (progn
 873                             (setq dotnum newnum)
 874                             (message "NNTP: Reading %s"
 875                                      (make-string dotnum ?.))))))
 876                 (nntp-accept-response)))
 877             ;; Remove "...".
 878             (if (and nntp-debug-read (> dotnum 0))
 879                 (message ""))
 880             ;; Successfully received server response.
 881             t)))))
 882
 883 \f
 884
 885 ;;;
 886 ;;; Low-Level Interface to NNTP Server.
 887 ;;;
 888
 889 (defun nntp-retrieve-headers-with-xover (sequence)
 890   (erase-buffer)
 891   (cond
 892
 893    ;; This server does not talk NOV.
 894    ((not nntp-server-xover)
 895     nil)
 896
 897    ;; We don't care about gaps.
 898    ((not nntp-nov-gap)
 899     (nntp-send-xover-command
 900      (car sequence) (nntp-last-element sequence) 'wait)
 901
 902     (goto-char (point-min))
 903     (if (looking-at "[1-5][0-9][0-9] ")
 904         (delete-region (point) (progn (forward-line 1) (point))))
 905     (while (search-forward "\r" nil t)
 906       (replace-match "" t t))
 907     (goto-char (point-max))
 908     (forward-line -1)
 909     (if (looking-at "\\.")
 910         (delete-region (point) (progn (forward-line 1) (point)))))
 911
 912    ;; We do it the hard way.  For each gap, an XOVER command is sent
 913    ;; to the server.  We do not wait for a reply from the server, we
 914    ;; just send them off as fast as we can.  That means that we have
 915    ;; to count the number of responses we get back to find out when we
 916    ;; have gotten all we asked for.
 917    ((numberp nntp-nov-gap)
 918     (let ((count 0)
 919           (received 0)
 920           (last-point (point-min))
 921           (buf (current-buffer))
 922           first)
 923       ;; We have to check `nntp-server-xover'.  If it gets set to nil,
 924       ;; that means that the server does not understand XOVER, but we
 925       ;; won't know that until we try.
 926       (while (and nntp-server-xover sequence)
 927         (setq first (car sequence))
 928         ;; Search forward until we find a gap, or until we run out of
 929         ;; articles.
 930         (while (and (cdr sequence)
 931                     (< (- (nth 1 sequence) (car sequence)) nntp-nov-gap))
 932           (setq sequence (cdr sequence)))
 933
 934         (if (not (nntp-send-xover-command first (car sequence)))
 935             ()
 936           (setq sequence (cdr sequence)
 937                 count (1+ count))
 938
 939           ;; Every 400 requests we have to read the stream in
 940           ;; order to avoid deadlocks.
 941           (if (or (null sequence)       ;All requests have been sent.
 942                   (zerop (% count nntp-maximum-request)))
 943               (progn
 944                 (accept-process-output)
 945                 ;; On some Emacs versions the preceding function has
 946                 ;; a tendency to change the buffer. Perhaps. It's
 947                 ;; quite difficult to reproduce, because it only
 948                 ;; seems to happen once in a blue moon.
 949                 (set-buffer buf)
 950                 (while (progn
 951                          (goto-char last-point)
 952                          ;; Count replies.
 953                          (while (re-search-forward "^[0-9][0-9][0-9] " nil t)
 954                            (setq received (1+ received)))
 955                          (setq last-point (point))
 956                          (< received count))
 957                   (accept-process-output)
 958                   (set-buffer buf))))))
 959
 960       (if (not nntp-server-xover)
 961           ()
 962         ;; Wait for the reply from the final command.
 963         (goto-char (point-max))
 964         (re-search-backward "^[0-9][0-9][0-9] " nil t)
 965         (if (looking-at "^[23]")
 966             (while (progn
 967                      (goto-char (point-max))
 968                      (forward-line -1)
 969                      (not (looking-at "^\\.\r?\n")))
 970               (nntp-accept-response)))
 971
 972         ;; We remove any "." lines and status lines.
 973         (goto-char (point-min))
 974         (while (search-forward "\r" nil t)
 975           (delete-char -1))
 976         (goto-char (point-min))
 977         (delete-matching-lines "^\\.$\\|^[1-5][0-9][0-9] ")))))
 978
 979   nntp-server-xover)
 980
 981 (defun nntp-send-xover-command (beg end &optional wait-for-reply)
 982   (let ((range (format "%d-%d" beg end)))
 983     (if (stringp nntp-server-xover)
 984         ;; If `nntp-server-xover' is a string, then we just send this
 985         ;; command.
 986         (if wait-for-reply
 987             (nntp-send-command "^\\.\r?\n" nntp-server-xover range)
 988           ;; We do not wait for the reply.
 989           (progn
 990             (nntp-send-strings-to-server nntp-server-xover range)
 991             t))
 992       (let ((commands nntp-xover-commands))
 993         ;; `nntp-xover-commands' is a list of possible XOVER commands.
 994         ;; We try them all until we get at positive response.
 995         (while (and commands (eq nntp-server-xover 'try))
 996           (nntp-send-command "^\\.\r?\n" (car commands) range)
 997           (save-excursion
 998             (set-buffer nntp-server-buffer)
 999             (goto-char (point-min))
1000             (and (looking-at "[23]") ; No error message.
1001                  ;; We also have to look at the lines.  Some buggy
1002                  ;; servers give back simple lines with just the
1003                  ;; article number.  How... helpful.
1004                  (progn
1005                    (forward-line 1)
1006                    (looking-at "[0-9]+\t...")) ; More text after number.
1007                  (setq nntp-server-xover (car commands))))
1008           (setq commands (cdr commands)))
1009         ;; If none of the commands worked, we disable XOVER.
1010         (if (eq nntp-server-xover 'try)
1011             (save-excursion
1012               (set-buffer nntp-server-buffer)
1013               (erase-buffer)
1014               (setq nntp-server-xover nil)))
1015         nntp-server-xover))))
1016
1017 (defun nntp-send-strings-to-server (&rest strings)
1018   "Send list of STRINGS to news server as command and its arguments."
1019   (let ((cmd (concat (mapconcat 'identity strings " ") "\r\n")))
1020     ;; We open the nntp server if it is down.
1021     (or (nntp-server-opened nntp-current-server)
1022         (nntp-open-server nntp-current-server)
1023         (error "%s" (nntp-status-message)))
1024     ;; Send the strings.
1025     (process-send-string nntp-server-process cmd)))
1026
1027 (defun nntp-send-region-to-server (begin end)
1028   "Send the current buffer region (from BEGIN to END) to the server."
1029   (save-excursion
1030     (let ((cur (current-buffer)))
1031       ;; Copy the buffer over to the send buffer.
1032       (set-buffer (get-buffer-create " *nntp send*"))
1033       (buffer-disable-undo (current-buffer))
1034       (erase-buffer)
1035       (insert-buffer-substring cur begin end)
1036       (save-excursion
1037         (set-buffer cur)
1038         (erase-buffer))
1039       ;; `process-send-region' does not work if the text to be sent is very
1040       ;; large, so we send it piecemeal.
1041       (let ((last (point-min))
1042             (size 100))                 ;Size of text sent at once.
1043         (while (/= last (point-max))
1044           (process-send-region
1045            nntp-server-process
1046            last (setq last (min (+ last size) (point-max))))
1047           ;; Read any output from the server.  May be unnecessary.
1048           (accept-process-output)))
1049       (kill-buffer (current-buffer)))))
1050
1051 (defun nntp-open-server-semi-internal (server &optional service)
1052   "Open SERVER.
1053 If SERVER is nil, use value of environment variable `NNTPSERVER'.
1054 If SERVICE, this this as the port number."
1055   (let ((server (or server (getenv "NNTPSERVER")))
1056         (status nil)
1057         (timer
1058          (and nntp-connection-timeout
1059               (cond
1060                ((fboundp 'run-at-time)
1061                 (run-at-time nntp-connection-timeout
1062                              nil 'nntp-kill-connection server))
1063                ((fboundp 'start-itimer)
1064                 ;; Not sure if this will work or not, only one way to
1065                 ;; find out
1066                 (eval '(start-itimer "nntp-timeout"
1067                                      (lambda ()
1068                                        (nntp-kill-connection server))
1069                                      nntp-connection-timeout nil)))))))
1070     (save-excursion
1071       (set-buffer nntp-server-buffer)
1072       (setq nntp-status-string "")
1073       (message "nntp: Connecting to server on %s..." server)
1074       (cond ((and server (nntp-open-server-internal server service))
1075              (setq nntp-address server)
1076              (setq status
1077                    (condition-case nil
1078                        (nntp-wait-for-response "^[23].*\r?\n" 'slow)
1079                      (error nil)
1080                      (quit nil)))
1081              (or status (nntp-close-server-internal server))
1082              (and nntp-server-process
1083                   (progn
1084                     (set-process-sentinel
1085                      nntp-server-process 'nntp-default-sentinel)
1086                     ;; You can send commands at startup like AUTHINFO here.
1087                     ;; Added by Hallvard B Furuseth <h.b.furuseth@usit.uio.no>
1088                     (run-hooks 'nntp-server-opened-hook))))
1089             ((null server)
1090              (setq nntp-status-string "NNTP server is not specified."))
1091             (t                          ; We couldn't open the server.
1092              (setq nntp-status-string
1093                    (buffer-substring (point-min) (point-max)))
1094              (setq nntp-timeout-servers (cons server nntp-timeout-servers))))
1095       (and timer (cancel-timer timer))
1096       (message "")
1097       (or status
1098           (setq nntp-current-server nil
1099                 nntp-async-number nil))
1100       status)))
1101
1102 (defun nntp-open-server-internal (server &optional service)
1103   "Open connection to news server on SERVER by SERVICE (default is nntp)."
1104   (let (proc)
1105     (save-excursion
1106       ;; Use TCP/IP stream emulation package if needed.
1107       (or (fboundp 'open-network-stream)
1108           (require 'tcp))
1109       ;; Initialize communication buffer.
1110       (nnheader-init-server-buffer)
1111       (set-buffer nntp-server-buffer)
1112       (if (setq proc
1113                 (condition-case nil
1114                     (funcall nntp-open-server-function server)
1115                   (error nil)))
1116           (progn
1117             (setq nntp-server-process proc)
1118             ;; Suggested by Hallvard B Furuseth <h.b.furuseth@usit.uio.no>.
1119             (process-kill-without-query proc)
1120             (setq nntp-address server)
1121             ;; It is possible to change kanji-fileio-code in this hook.
1122             (run-hooks 'nntp-server-hook)
1123             (push proc nntp-opened-connections)
1124             nntp-server-process)))))
1125
1126 (defun nntp-open-network-stream (server)
1127   (open-network-stream
1128    "nntpd" nntp-server-buffer server nntp-port-number))
1129
1130 (defun nntp-open-rlogin (server)
1131   (let ((proc (start-process "nntpd" nntp-server-buffer "rsh" server)))
1132     (process-send-string proc (mapconcat 'identity nntp-rlogin-parameters
1133                                          " "))
1134     (process-send-string proc "\n")))
1135
1136 (defun nntp-telnet-to-machine ()
1137   (let (b)
1138     (telnet "localhost")
1139     (goto-char (point-min))
1140     (while (not (re-search-forward "^login: *" nil t))
1141       (sit-for 1)
1142       (goto-char (point-min)))
1143     (goto-char (point-max))
1144     (insert "larsi")
1145     (telnet-send-input)
1146     (setq b (point))
1147     (while (not (re-search-forward ">" nil t))
1148       (sit-for 1)
1149       (goto-char b))
1150     (goto-char (point-max))
1151     (insert "ls")
1152     (telnet-send-input)))
1153
1154 (defun nntp-close-server-internal (&optional server)
1155   "Close connection to news server."
1156   (nntp-possibly-change-server nil server)
1157   (if nntp-server-process
1158       (delete-process nntp-server-process))
1159   (setq nntp-server-process nil)
1160   (setq nntp-address ""))
1161
1162 (defun nntp-accept-response ()
1163   "Read response of server.
1164 It is well-known that the communication speed will be much improved by
1165 defining this function as macro."
1166   ;; To deal with server process exiting before
1167   ;;  accept-process-output is called.
1168   ;; Suggested by Jason Venner <jason@violet.berkeley.edu>.
1169   ;; This is a copy of `nntp-default-sentinel'.
1170   (let ((buf (current-buffer)))
1171     (prog1
1172         (if (or (not nntp-server-process)
1173                 (not (memq (process-status nntp-server-process) '(open run))))
1174             (error "nntp: Process connection closed; %s" (nntp-status-message))
1175           (if nntp-buggy-select
1176               (progn
1177                 ;; We cannot use `accept-process-output'.
1178                 ;; Fujitsu UTS requires messages during sleep-for.
1179                 ;; I don't know why.
1180                 (message "NNTP: Reading...")
1181                 (sleep-for 1)
1182                 (message ""))
1183             (condition-case errorcode
1184                 (accept-process-output nntp-server-process 1)
1185               (error
1186                (cond ((string-equal "select error: Invalid argument"
1187                                     (nth 1 errorcode))
1188                       ;; Ignore select error.
1189                       nil)
1190                      (t
1191                       (signal (car errorcode) (cdr errorcode))))))))
1192       (set-buffer buf))))
1193
1194 (defun nntp-last-element (list)
1195   "Return last element of LIST."
1196   (while (cdr list)
1197     (setq list (cdr list)))
1198   (car list))
1199
1200 (defun nntp-possibly-change-server (newsgroup server &optional connectionless)
1201   "Check whether the virtual server needs changing."
1202   (if (and server
1203            (not (nntp-server-opened server)))
1204       ;; This virtual server isn't open, so we (re)open it here.
1205       (nntp-open-server server nil t))
1206   (if (and newsgroup
1207            (not (equal newsgroup nntp-current-group)))
1208       ;; Set the proper current group.
1209       (nntp-request-group newsgroup server)))
1210
1211 (defun nntp-try-list-active (group)
1212   (nntp-list-active-group group)
1213   (save-excursion
1214     (set-buffer nntp-server-buffer)
1215     (goto-char (point-min))
1216     (cond ((looking-at "5[0-9]+")
1217            (setq nntp-server-list-active-group nil))
1218           (t
1219            (setq nntp-server-list-active-group t)))))
1220
1221 (defun nntp-async-server-opened ()
1222   (and nntp-async-process
1223        (memq (process-status nntp-async-process) '(open run))))
1224
1225 (defun nntp-async-open-server ()
1226   (save-excursion
1227     (set-buffer (generate-new-buffer " *async-nntp*"))
1228     (setq nntp-async-buffer (current-buffer))
1229     (buffer-disable-undo (current-buffer)))
1230   (let ((nntp-server-process nil)
1231         (nntp-server-buffer nntp-async-buffer))
1232     (nntp-open-server-semi-internal nntp-address nntp-port-number)
1233     (if (not (setq nntp-async-process nntp-server-process))
1234         (progn
1235           (setq nntp-async-number nil))
1236       (set-process-buffer nntp-async-process nntp-async-buffer))))
1237
1238 (defun nntp-async-fetch-articles (article)
1239   (if (stringp article)
1240       ()
1241     (let ((articles (cdr (memq (assq article nntp-async-articles)
1242                                nntp-async-articles)))
1243           (max (cond ((numberp nntp-async-number)
1244                       nntp-async-number)
1245                      ((eq nntp-async-number t)
1246                       (length nntp-async-articles))
1247                      (t 0)))
1248           nart)
1249       (while (and (>= (setq max (1- max)) 0)
1250                   articles)
1251         (or (memq (setq nart (car (car articles))) nntp-async-fetched)
1252             (progn
1253               (nntp-async-send-strings "ARTICLE " (int-to-string nart))
1254               (setq nntp-async-fetched (cons nart nntp-async-fetched))))
1255         (setq articles (cdr articles))))))
1256
1257 (defun nntp-async-send-strings (&rest strings)
1258   (let ((cmd (concat (mapconcat 'identity strings " ") "\r\n")))
1259     (or (nntp-async-server-opened)
1260         (nntp-async-open-server)
1261         (error "%s" (nntp-status-message)))
1262     (process-send-string nntp-async-process cmd)))
1263
1264 (defun nntp-async-request-group (group)
1265   (if (equal group nntp-current-group)
1266       ()
1267     (let ((asyncs (assoc group nntp-async-group-alist)))
1268       ;; A new group has been selected, so we push the current state
1269       ;; of async articles on an alist, and pull the old state off.
1270       (setq nntp-async-group-alist
1271             (cons (list nntp-current-group
1272                         nntp-async-articles nntp-async-fetched
1273                         nntp-async-process)
1274                   (delq asyncs nntp-async-group-alist)))
1275       (and asyncs
1276            (progn
1277              (setq nntp-async-articles (nth 1 asyncs))
1278              (setq nntp-async-fetched (nth 2 asyncs))
1279              (setq nntp-async-process (nth 3 asyncs)))))))
1280
1281 (provide 'nntp)
1282
1283 ;;; nntp.el ends here