[gnu-emacs] / lisp / gnus / nnspool.el

;;; nnspool.el --- spool access for GNU Emacs

;; Copyright (C) 1988, 1989, 1990, 1993, 1994, 1995, 1996, 1997, 1998,
;;   2000, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.

;; Author: Masanobu UMEDA <umerin@flab.flab.fujitsu.junet>
;;      Lars Magne Ingebrigtsen <larsi@gnus.org>
;; Keywords: news

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;;; Commentary:

;;; Code:

(require 'nnheader)
(require 'nntp)
(require 'nnoo)
(eval-when-compile (require 'cl))

(nnoo-declare nnspool)

(defvoo nnspool-inews-program news-inews-program
  "Program to post news.
This is most commonly `inews' or `injnews'.")

(defvoo nnspool-inews-switches '("-h" "-S")
  "Switches for nnspool-request-post to pass to `inews' for posting news.
If you are using Cnews, you probably should set this variable to nil.")

(defvoo nnspool-spool-directory
    (file-name-as-directory (if (boundp 'news-directory)
                                (symbol-value 'news-directory)
                              news-path))
  "Local news spool directory.")

(defvoo nnspool-nov-directory (concat nnspool-spool-directory "over.view/")
  "Local news nov directory.")

(defvoo nnspool-lib-dir
    (if (file-exists-p "/usr/lib/news/active")
        "/usr/lib/news/"
      "/var/lib/news/")
  "Where the local news library files are stored.")

(defvoo nnspool-active-file (concat nnspool-lib-dir "active")
  "Local news active file.")

(defvoo nnspool-newsgroups-file (concat nnspool-lib-dir "newsgroups")
  "Local news newsgroups file.")

(defvoo nnspool-distributions-file (concat nnspool-lib-dir "distribs.pat")
  "Local news distributions file.")

(defvoo nnspool-history-file (concat nnspool-lib-dir "history")
  "Local news history file.")

(defvoo nnspool-active-times-file (concat nnspool-lib-dir "active.times")
  "Local news active date file.")

(defvoo nnspool-large-newsgroup 50
  "The number of articles which indicates a large newsgroup.
If the number of articles is greater than the value, verbose
messages will be shown to indicate the current status.")

(defvoo nnspool-nov-is-evil nil
  "Non-nil means that nnspool will never return NOV lines instead of headers.")

(defconst nnspool-sift-nov-with-sed nil
  "If non-nil, use sed to get the relevant portion from the overview file.
If nil, nnspool will load the entire file into a buffer and process it
there.")

(defvoo nnspool-rejected-article-hook nil
  "*A hook that will be run when an article has been rejected by the server.")

(defvoo nnspool-file-coding-system nnheader-file-coding-system
  "Coding system for nnspool.")

\f

(defconst nnspool-version "nnspool 2.0"
  "Version numbers of this version of NNSPOOL.")

(defvoo nnspool-current-directory nil
  "Current news group directory.")

(defvoo nnspool-current-group nil)
(defvoo nnspool-status-string "")

\f
;;; Interface functions.

(nnoo-define-basics nnspool)

(deffoo nnspool-retrieve-headers (articles &optional group server fetch-old)
  "Retrieve the headers of ARTICLES."
  (save-excursion
    (set-buffer nntp-server-buffer)
    (erase-buffer)
    (when (nnspool-possibly-change-directory group)
      (let* ((number (length articles))
             (count 0)
             (default-directory nnspool-current-directory)
             (do-message (and (numberp nnspool-large-newsgroup)
                              (> number nnspool-large-newsgroup)))
             (nnheader-file-coding-system nnspool-file-coding-system)
             file beg article ag)
        (if (and (numberp (car articles))
                 (nnspool-retrieve-headers-with-nov articles fetch-old))
            ;; We successfully retrieved the NOV headers.
            'nov
          ;; No NOV headers here, so we do it the hard way.
          (while (setq article (pop articles))
            (if (stringp article)
                ;; This is a Message-ID.
                (setq ag (nnspool-find-id article)
                      file (and ag (nnspool-article-pathname
                                    (car ag) (cdr ag)))
                      article (cdr ag))
              ;; This is an article in the current group.
              (setq file (int-to-string article)))
            ;; Insert the head of the article.
            (when (and file
                       (file-exists-p file))
              (insert "221 ")
              (princ article (current-buffer))
              (insert " Article retrieved.\n")
              (setq beg (point))
              (inline (nnheader-insert-head file))
              (goto-char beg)
              (if (search-forward "\n\n" nil t)
                  (progn
                    (forward-char -1)
                    (insert ".\n"))
                (goto-char (point-max))
                (if (bolp)
                    (insert ".\n")
                  (insert "\n.\n")))
              (delete-region (point) (point-max)))

            (and do-message
                 (zerop (% (incf count) 20))
                 (nnheader-message 5 "nnspool: Receiving headers... %d%%"
                                   (/ (* count 100) number))))

          (when do-message
            (nnheader-message 5 "nnspool: Receiving headers...done"))

          ;; Fold continuation lines.
          (nnheader-fold-continuation-lines)
          'headers)))))

(deffoo nnspool-open-server (server &optional defs)
  (nnoo-change-server 'nnspool server defs)
  (cond
   ((not (file-exists-p nnspool-spool-directory))
    (nnspool-close-server)
    (nnheader-report 'nnspool "Spool directory doesn't exist: %s"
                     nnspool-spool-directory))
   ((not (file-directory-p
          (directory-file-name
           (file-truename nnspool-spool-directory))))
    (nnspool-close-server)
    (nnheader-report 'nnspool "Not a directory: %s" nnspool-spool-directory))
   ((not (file-exists-p nnspool-active-file))
    (nnheader-report 'nnspool "The active file doesn't exist: %s"
                     nnspool-active-file))
   (t
    (nnheader-report 'nnspool "Opened server %s using directory %s"
                     server nnspool-spool-directory)
    t)))

(deffoo nnspool-request-article (id &optional group server buffer)
  "Select article by message ID (or number)."
  (nnspool-possibly-change-directory group)
  (let ((nntp-server-buffer (or buffer nntp-server-buffer))
        file ag)
    (if (stringp id)
        ;; This is a Message-ID.
        (when (setq ag (nnspool-find-id id))
          (setq file (nnspool-article-pathname (car ag) (cdr ag))))
      (setq file (nnspool-article-pathname nnspool-current-group id)))
    (and file
         (file-exists-p file)
         (not (file-directory-p file))
         (save-excursion (nnspool-find-file file))
         ;; We return the article number and group name.
         (if (numberp id)
             (cons nnspool-current-group id)
           ag))))

(deffoo nnspool-request-body (id &optional group server)
  "Select article body by message ID (or number)."
  (nnspool-possibly-change-directory group)
  (let ((res (nnspool-request-article id)))
    (when res
      (save-excursion
        (set-buffer nntp-server-buffer)
        (goto-char (point-min))
        (when (search-forward "\n\n" nil t)
          (delete-region (point-min) (point)))
        res))))

(deffoo nnspool-request-head (id &optional group server)
  "Select article head by message ID (or number)."
  (nnspool-possibly-change-directory group)
  (let ((res (nnspool-request-article id)))
    (when res
      (save-excursion
        (set-buffer nntp-server-buffer)
        (goto-char (point-min))
        (when (search-forward "\n\n" nil t)
          (delete-region (1- (point)) (point-max)))
        (nnheader-fold-continuation-lines)))
    res))

(deffoo nnspool-request-group (group &optional server dont-check)
  "Select news GROUP."
  (let ((pathname (nnspool-article-pathname group))
        dir)
    (if (not (file-directory-p pathname))
        (nnheader-report
         'nnspool "Invalid group name (no such directory): %s" group)
      (setq nnspool-current-directory pathname)
      (nnheader-report 'nnspool "Selected group %s" group)
      (if dont-check
          (progn
            (nnheader-report 'nnspool "Selected group %s" group)
            t)
        ;; Yes, completely empty spool directories *are* possible.
        ;; Fix by Sudish Joseph <joseph@cis.ohio-state.edu>
        (when (setq dir (directory-files pathname nil "^[0-9]+$" t))
          (setq dir
                (sort (mapcar (lambda (name) (string-to-number name)) dir) '<)))
        (if dir
            (nnheader-insert
             "211 %d %d %d %s\n" (length dir) (car dir)
             (progn (while (cdr dir) (setq dir (cdr dir))) (car dir))
             group)
          (nnheader-report 'nnspool "Empty group %s" group)
          (nnheader-insert "211 0 0 0 %s\n" group))))))

(deffoo nnspool-request-type (group &optional article)
  'news)

(deffoo nnspool-close-group (group &optional server)
  t)

(deffoo nnspool-request-list (&optional server)
  "List active newsgroups."
  (save-excursion
    (or (nnspool-find-file nnspool-active-file)
        (nnheader-report 'nnspool (nnheader-file-error nnspool-active-file)))))

(deffoo nnspool-request-list-newsgroups (&optional server)
  "List newsgroups (defined in NNTP2)."
  (save-excursion
    (or (nnspool-find-file nnspool-newsgroups-file)
        (nnheader-report 'nnspool (nnheader-file-error
                                   nnspool-newsgroups-file)))))

(deffoo nnspool-request-list-distributions (&optional server)
  "List distributions (defined in NNTP2)."
  (save-excursion
    (or (nnspool-find-file nnspool-distributions-file)
        (nnheader-report 'nnspool (nnheader-file-error
                                   nnspool-distributions-file)))))

;; Suggested by Hallvard B Furuseth <h.b.furuseth@usit.uio.no>.
(deffoo nnspool-request-newgroups (date &optional server)
  "List groups created after DATE."
  (if (nnspool-find-file nnspool-active-times-file)
      (save-excursion
        ;; Find the last valid line.
        (goto-char (point-max))
        (while (and (not (looking-at
                          "\\([^ ]+\\) +\\([0-9]+\\)[0-9][0-9][0-9] "))
                    (zerop (forward-line -1))))
        (let ((seconds (time-to-seconds (date-to-time date)))
              groups)
          ;; Go through lines and add the latest groups to a list.
          (while (and (looking-at "\\([^ ]+\\) +[0-9]+ ")
                      (progn
                        ;; We insert a .0 to make the list reader
                        ;; interpret the number as a float.  It is far
                        ;; too big to be stored in a lisp integer.
                        (goto-char (1- (match-end 0)))
                        (insert ".0")
                        (> (progn
                             (goto-char (match-end 1))
                             (read (current-buffer)))
                           seconds))
                      (push (buffer-substring
                             (match-beginning 1) (match-end 1))
                            groups)
                      (zerop (forward-line -1))))
          (erase-buffer)
          (while groups
            (insert (car groups) " 0 0 y\n")
            (setq groups (cdr groups))))
        t)
    nil))

(deffoo nnspool-request-post (&optional server)
  "Post a new news in current buffer."
  (save-excursion
    (let* ((process-connection-type nil) ; t bugs out on Solaris
           (inews-buffer (generate-new-buffer " *nnspool post*"))
           (proc
            (condition-case err
                (apply 'start-process "*nnspool inews*" inews-buffer
                       nnspool-inews-program nnspool-inews-switches)
              (error
               (nnheader-report 'nnspool "inews error: %S" err)))))
      (if (not proc)
          ;; The inews program failed.
          ()
        (nnheader-report 'nnspool "")
        (set-process-sentinel proc 'nnspool-inews-sentinel)
        (mm-with-unibyte-current-buffer
          (process-send-region proc (point-min) (point-max)))
        ;; We slap a condition-case around this, because the process may
        ;; have exited already...
        (ignore-errors
          (process-send-eof proc))
        t))))


\f
;;; Internal functions.

(defun nnspool-inews-sentinel (proc status)
  (save-excursion
    (set-buffer (process-buffer proc))
    (goto-char (point-min))
    (if (or (zerop (buffer-size))
            (search-forward "spooled" nil t))
        (kill-buffer (current-buffer))
      ;; Make status message by folding lines.
      (while (re-search-forward "[ \t\n]+" nil t)
        (replace-match " " t t))
      (nnheader-report 'nnspool "%s" (buffer-string))
      (nnheader-message 5 "nnspool: %s" nnspool-status-string)
      (ding)
      (run-hooks 'nnspool-rejected-article-hook))))

(defun nnspool-retrieve-headers-with-nov (articles &optional fetch-old)
  (if (or gnus-nov-is-evil nnspool-nov-is-evil)
      nil
    (let ((nov (nnheader-group-pathname
                nnspool-current-group nnspool-nov-directory ".overview"))
          (arts articles)
          (nnheader-file-coding-system nnspool-file-coding-system)
          last)
      (if (not (file-exists-p nov))
          ()
        (save-excursion
          (set-buffer nntp-server-buffer)
          (erase-buffer)
          (if nnspool-sift-nov-with-sed
              (nnspool-sift-nov-with-sed articles nov)
            (nnheader-insert-file-contents nov)
            (if (and fetch-old
                     (not (numberp fetch-old)))
                t                       ; We want all the headers.
              (ignore-errors
                ;; Delete unwanted NOV lines.
                (nnheader-nov-delete-outside-range
                 (if fetch-old (max 1 (- (car articles) fetch-old))
                   (car articles))
                 (car (last articles)))
                ;; If the buffer is empty, this wasn't very successful.
                (unless (zerop (buffer-size))
                  ;; We check what the last article number was.
                  ;; The NOV file may be out of sync with the articles
                  ;; in the group.
                  (forward-line -1)
                  (setq last (read (current-buffer)))
                  (if (= last (car articles))
                      ;; Yup, it's all there.
                      t
                    ;; Perhaps not.  We try to find the missing articles.
                    (while (and arts
                                (<= last (car arts)))
                      (pop arts))
                    ;; The articles in `arts' are missing from the buffer.
                    (while arts
                      (nnspool-insert-nov-head (pop arts)))
                    t))))))))))

(defun nnspool-insert-nov-head (article)
  "Read the head of ARTICLE, convert to NOV headers, and insert."
  (save-excursion
    (let ((cur (current-buffer))
          buf)
      (setq buf (nnheader-set-temp-buffer " *nnspool head*"))
      (when (nnheader-insert-head
             (nnspool-article-pathname nnspool-current-group article))
        (nnheader-insert-article-line article)
        (let ((headers (nnheader-parse-head)))
          (set-buffer cur)
          (goto-char (point-max))
          (nnheader-insert-nov headers)))
      (kill-buffer buf))))

(defun nnspool-sift-nov-with-sed (articles file)
  (let ((first (car articles))
        (last (progn (while (cdr articles) (setq articles (cdr articles)))
                     (car articles))))
    (call-process "awk" nil t nil
                  (format "BEGIN {firstmsg=%d; lastmsg=%d;}\n $1 >= firstmsg && $1 <= lastmsg {print;}"
                          (1- first) (1+ last))
                  file)))

;; Fixed by fdc@cliwe.ping.de (Frank D. Cringle).
;; Find out what group an article identified by a Message-ID is in.
(defun nnspool-find-id (id)
  (save-excursion
    (set-buffer (get-buffer-create " *nnspool work*"))
    (erase-buffer)
    (ignore-errors
      (call-process "grep" nil t nil (regexp-quote id) nnspool-history-file))
    (goto-char (point-min))
    (prog1
        (when (looking-at "<[^>]+>[ \t]+[-0-9~]+[ \t]+\\([^ /\t\n]+\\)/\\([0-9]+\\)[ \t\n]")
          (cons (match-string 1) (string-to-number (match-string 2))))
      (kill-buffer (current-buffer)))))

(defun nnspool-find-file (file)
  "Insert FILE in server buffer safely."
  (set-buffer nntp-server-buffer)
  (erase-buffer)
  (condition-case ()
      (let ((coding-system-for-read nnspool-file-coding-system))
        (mm-insert-file-contents file)
        t)
    (file-error nil)))

(defun nnspool-possibly-change-directory (group)
  (if (not group)
      t
    (let ((pathname (nnspool-article-pathname group)))
      (if (file-directory-p pathname)
          (setq nnspool-current-directory pathname
                nnspool-current-group group)
        (nnheader-report 'nnspool "No such newsgroup: %s" group)))))

(defun nnspool-article-pathname (group &optional article)
  "Find the file name for GROUP."
  (nnheader-group-pathname group nnspool-spool-directory article))

(provide 'nnspool)

;;; arch-tag: bdac8d27-2934-4eee-bad0-49e6b90c0d05
;;; nnspool.el ends here