lisp/url/url-news.el

   1 ;;; url-news.el --- News Uniform Resource Locator retrieval code
   2
   3 ;; Copyright (C) 1996-1999, 2004-2018 Free Software Foundation, Inc.
   4
   5 ;; Keywords: comm, data, processes
   6
   7 ;; This file is part of GNU Emacs.
   8
   9 ;; GNU Emacs is free software: you can redistribute it and/or modify
  10 ;; it under the terms of the GNU General Public License as published by
  11 ;; the Free Software Foundation, either version 3 of the License, or
  12 ;; (at your option) any later version.
  13
  14 ;; GNU Emacs is distributed in the hope that it will be useful,
  15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 ;; GNU General Public License for more details.
  18
  19 ;; You should have received a copy of the GNU General Public License
  20 ;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
  21
  22 ;;; Code:
  23
  24 (require 'url-vars)
  25 (require 'url-util)
  26 (require 'url-parse)
  27 (require 'nntp)
  28 (autoload 'url-warn "url")
  29 (autoload 'gnus-group-read-ephemeral-group "gnus-group")
  30
  31 ;; Unused.
  32 ;;; (defgroup url-news nil
  33 ;;;   "News related options."
  34 ;;;   :group 'url)
  35
  36 (defun url-news-open-host (host port user pass)
  37   (if (fboundp 'nnheader-init-server-buffer)
  38       (nnheader-init-server-buffer))
  39   (nntp-open-server host (list port))
  40   (if (and user pass)
  41       (progn
  42         (nntp-send-command "^.*\r?\n" "AUTHINFO USER" user)
  43         (nntp-send-command "^.*\r?\n" "AUTHINFO PASS" pass)
  44         (if (not (nntp-server-opened host))
  45             (url-warn 'url (format "NNTP authentication to `%s' as `%s' failed"
  46                                    host user))))))
  47
  48 (defun url-news-fetch-message-id (host message-id)
  49   (let ((buf (generate-new-buffer " *url-news*")))
  50     (if (eq ?> (aref message-id (1- (length message-id))))
  51         nil
  52       (setq message-id (concat "<" message-id ">")))
  53     (if (cdr-safe (nntp-request-article message-id nil host buf))
  54         ;; Successfully retrieved the article
  55         nil
  56       (with-current-buffer buf
  57         (insert "Content-type: text/html\n\n"
  58                 "<html>\n"
  59                 " <head>\n"
  60                 "  <title>Error</title>\n"
  61                 " </head>\n"
  62                 " <body>\n"
  63                 "  <div>\n"
  64                 "   <h1>Error requesting article...</h1>\n"
  65                 "   <p>\n"
  66                 "    The status message returned by the NNTP server was:"
  67                 "<br><hr>\n"
  68                 "    <xmp>\n"
  69                 (nntp-status-message)
  70                 "    </xmp>\n"
  71                 "   </p>\n"
  72                 "   <p>\n"
  73                 "    If you feel this is an error, M-x report-emacs-bug RET.\n"
  74                 "   </p>\n"
  75                 "  </div>\n"
  76                 " </body>\n"
  77                 "</html>\n"
  78                 "<!-- Automatically generated by URL v" url-version " -->\n"
  79                 )))
  80     buf))
  81
  82 (defvar gnus-group-buffer)
  83
  84 (defun url-news-fetch-newsgroup (newsgroup host)
  85   (if (string-match "^/+" newsgroup)
  86       (setq newsgroup (substring newsgroup (match-end 0))))
  87   (if (string-match "/+$" newsgroup)
  88       (setq newsgroup (substring newsgroup 0 (match-beginning 0))))
  89
  90   ;; This saves us from checking new news if Gnus is already running
  91   ;; FIXME - is it relatively safe to use gnus-alive-p here? FIXME
  92   (if (or (not (get-buffer gnus-group-buffer))
  93           (with-current-buffer gnus-group-buffer
  94             (not (eq major-mode 'gnus-group-mode))))
  95       (gnus))
  96   (set-buffer gnus-group-buffer)
  97   (goto-char (point-min))
  98   (gnus-group-read-ephemeral-group newsgroup
  99                                    (list 'nntp host
 100                                          (list 'nntp-open-connection-function
 101                                                nntp-open-connection-function))
 102                                    nil
 103                                    (cons (current-buffer) 'browse)))
 104
 105 ;;;###autoload
 106 (defun url-news (url)
 107   ;; Find a news reference
 108   (let* ((host (or (url-host url) url-news-server))
 109          (port (url-port url))
 110          (article-brackets nil)
 111          (buf nil)
 112          (article (url-unhex-string (url-filename url))))
 113     (url-news-open-host host port (url-user url) (url-password url))
 114     (cond
 115      ((string-match "@" article)        ; Its a specific article
 116       (setq buf (url-news-fetch-message-id host article)))
 117      ((string= article "")              ; List all newsgroups
 118       (gnus))
 119      (t                                 ; Whole newsgroup
 120       (url-news-fetch-newsgroup article host)))
 121     buf))
 122
 123 ;;;###autoload
 124 (defun url-snews (url)
 125   (let ((nntp-open-connection-function (if (eq 'ssl url-gateway-method)
 126                                            'nntp-open-ssl-stream
 127                                          'nntp-open-tls-stream)))
 128     (url-news url)))
 129
 130 (provide 'url-news)
 131
 132 ;;; url-news.el ends here