lisp/gnus/nnmbox.el

   1 ;;; nnmbox.el --- mail mbox access for Gnus
   2
   3 ;; Copyright (C) 1995-2015 Free Software Foundation, Inc.
   4
   5 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
   6 ;;      Masanobu UMEDA <umerin@flab.flab.fujitsu.junet>
   7 ;; Keywords: news, mail
   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 3 of the License, or
  14 ;; (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; For an overview of what the interface functions do, please see the
  27 ;; Gnus sources.
  28
  29 ;;; Code:
  30
  31 (require 'nnheader)
  32 (require 'message)
  33 (require 'nnmail)
  34 (require 'nnoo)
  35 (require 'gnus-range)
  36 (eval-when-compile (require 'cl))
  37
  38 (nnoo-declare nnmbox)
  39
  40 (defvoo nnmbox-mbox-file (expand-file-name "~/mbox")
  41   "The name of the mail box file in the user's home directory.")
  42
  43 (defvoo nnmbox-active-file (expand-file-name "~/.mbox-active")
  44   "The name of the active file for the mail box.")
  45
  46 (defvoo nnmbox-get-new-mail t
  47   "If non-nil, nnmbox will check the incoming mail file and split the mail.")
  48
  49 (defvoo nnmbox-prepare-save-mail-hook nil
  50   "Hook run narrowed to an article before saving.")
  51
  52 \f
  53
  54 (defconst nnmbox-version "nnmbox 1.0"
  55   "nnmbox version.")
  56
  57 (defvoo nnmbox-current-group nil
  58   "Current nnmbox news group directory.")
  59
  60 (defvar nnmbox-mbox-buffer nil)
  61
  62 (defvoo nnmbox-status-string "")
  63
  64 (defvoo nnmbox-group-alist nil)
  65 (defvoo nnmbox-active-timestamp nil)
  66
  67 (defvoo nnmbox-file-coding-system mm-binary-coding-system)
  68 (defvoo nnmbox-file-coding-system-for-write nil)
  69 (defvoo nnmbox-active-file-coding-system mm-binary-coding-system)
  70 (defvoo nnmbox-active-file-coding-system-for-write nil)
  71
  72 (defvar nnmbox-group-building-active-articles nil)
  73 (defvar nnmbox-group-active-articles nil)
  74 \f
  75
  76 ;;; Interface functions
  77
  78 (nnoo-define-basics nnmbox)
  79
  80 (deffoo nnmbox-retrieve-headers (sequence &optional newsgroup server fetch-old)
  81   (with-current-buffer nntp-server-buffer
  82     (erase-buffer)
  83     (let ((number (length sequence))
  84           (count 0)
  85           article start stop)
  86       (nnmbox-possibly-change-newsgroup newsgroup server)
  87       (while sequence
  88         (setq article (car sequence))
  89         (set-buffer nnmbox-mbox-buffer)
  90         (when (nnmbox-find-article article)
  91           (setq start
  92                 (save-excursion
  93                   (re-search-backward
  94                    (concat "^" message-unix-mail-delimiter) nil t)
  95                   (point)))
  96           (search-forward "\n\n" nil t)
  97           (setq stop (1- (point)))
  98           (set-buffer nntp-server-buffer)
  99           (insert (format "221 %d Article retrieved.\n" article))
 100           (insert-buffer-substring nnmbox-mbox-buffer start stop)
 101           (goto-char (point-max))
 102           (insert ".\n"))
 103         (setq sequence (cdr sequence))
 104         (setq count (1+ count))
 105         (and (numberp nnmail-large-newsgroup)
 106              (> number nnmail-large-newsgroup)
 107              (zerop (% count 20))
 108              (nnheader-message 5 "nnmbox: Receiving headers... %d%%"
 109                                (floor (* count 100.0) number))))
 110
 111       (and (numberp nnmail-large-newsgroup)
 112            (> number nnmail-large-newsgroup)
 113            (nnheader-message 5 "nnmbox: Receiving headers...done"))
 114
 115       (set-buffer nntp-server-buffer)
 116       (nnheader-fold-continuation-lines)
 117       'headers)))
 118
 119 (deffoo nnmbox-open-server (server &optional defs)
 120   (nnoo-change-server 'nnmbox server defs)
 121   (nnmbox-create-mbox)
 122   (cond
 123    ((not (file-exists-p nnmbox-mbox-file))
 124     (nnmbox-close-server)
 125     (nnheader-report 'nnmbox "No such file: %s" nnmbox-mbox-file))
 126    ((file-directory-p nnmbox-mbox-file)
 127     (nnmbox-close-server)
 128     (nnheader-report 'nnmbox "Not a regular file: %s" nnmbox-mbox-file))
 129    (t
 130     (nnheader-report 'nnmbox "Opened server %s using mbox %s" server
 131                      nnmbox-mbox-file)
 132     t)))
 133
 134 (deffoo nnmbox-close-server (&optional server)
 135   (when (and nnmbox-mbox-buffer
 136              (buffer-name nnmbox-mbox-buffer))
 137     (kill-buffer nnmbox-mbox-buffer))
 138   (nnoo-close-server 'nnmbox server)
 139   t)
 140
 141 (deffoo nnmbox-server-opened (&optional server)
 142   (and (nnoo-current-server-p 'nnmbox server)
 143        nnmbox-mbox-buffer
 144        (buffer-name nnmbox-mbox-buffer)
 145        nntp-server-buffer
 146        (buffer-name nntp-server-buffer)))
 147
 148 (deffoo nnmbox-request-article (article &optional newsgroup server buffer)
 149   (nnmbox-possibly-change-newsgroup newsgroup server)
 150   (with-current-buffer nnmbox-mbox-buffer
 151     (save-excursion
 152       (when (nnmbox-find-article article)
 153         (let (start stop)
 154           (re-search-backward (concat "^" message-unix-mail-delimiter) nil t)
 155           (setq start (point))
 156           (forward-line 1)
 157           (setq stop (if (re-search-forward (concat "^"
 158                                                     message-unix-mail-delimiter)
 159                                             nil 'move)
 160                          (match-beginning 0)
 161                        (point)))
 162           (let ((nntp-server-buffer (or buffer nntp-server-buffer)))
 163             (set-buffer nntp-server-buffer)
 164             (erase-buffer)
 165             (insert-buffer-substring nnmbox-mbox-buffer start stop)
 166             (goto-char (point-min))
 167             (while (looking-at "From ")
 168               (delete-char 5)
 169               (insert "X-From-Line: ")
 170               (forward-line 1))
 171             (if (numberp article)
 172                 (cons nnmbox-current-group article)
 173               (nnmbox-article-group-number nil))))))))
 174
 175 (deffoo nnmbox-request-group (group &optional server dont-check info)
 176   (nnmbox-possibly-change-newsgroup nil server)
 177   (let ((active (cadr (assoc group nnmbox-group-alist))))
 178     (cond
 179      ((or (null active)
 180           (null (nnmbox-possibly-change-newsgroup group server)))
 181       (nnheader-report 'nnmbox "No such group: %s" group))
 182      (dont-check
 183       (nnheader-report 'nnmbox "Selected group %s" group)
 184       (nnheader-insert ""))
 185      (t
 186       (nnheader-report 'nnmbox "Selected group %s" group)
 187       (nnheader-insert "211 %d %d %d %s\n"
 188                        (1+ (- (cdr active) (car active)))
 189                        (car active) (cdr active) group)))))
 190
 191 (defun nnmbox-save-buffer ()
 192   (let ((coding-system-for-write
 193          (or nnmbox-file-coding-system-for-write
 194              nnmbox-file-coding-system)))
 195     (save-buffer)))
 196
 197 (defun nnmbox-save-active (group-alist active-file)
 198   (let ((nnmail-active-file-coding-system
 199          (or nnmbox-active-file-coding-system-for-write
 200              nnmbox-active-file-coding-system)))
 201     (nnmail-save-active group-alist active-file)))
 202
 203 (deffoo nnmbox-request-scan (&optional group server)
 204   (nnmbox-possibly-change-newsgroup group server)
 205   (nnmbox-read-mbox)
 206   (nnmail-get-new-mail
 207    'nnmbox
 208    (lambda ()
 209      (with-current-buffer nnmbox-mbox-buffer
 210        (nnmbox-save-buffer)))
 211    (file-name-directory nnmbox-mbox-file)
 212    group
 213    (lambda ()
 214      (save-excursion
 215        (let ((in-buf (current-buffer)))
 216          (set-buffer nnmbox-mbox-buffer)
 217          (goto-char (point-max))
 218          (insert-buffer-substring in-buf)))
 219      (nnmbox-save-active nnmbox-group-alist nnmbox-active-file))))
 220
 221 (deffoo nnmbox-close-group (group &optional server)
 222   t)
 223
 224 (deffoo nnmbox-request-create-group (group &optional server args)
 225   (nnmail-activate 'nnmbox)
 226   (unless (assoc group nnmbox-group-alist)
 227     (push (list group (cons 1 0))
 228           nnmbox-group-alist)
 229     (nnmbox-save-active nnmbox-group-alist nnmbox-active-file))
 230   t)
 231
 232 (deffoo nnmbox-request-list (&optional server)
 233   (save-excursion
 234     (let ((nnmail-file-coding-system
 235            nnmbox-active-file-coding-system))
 236       (nnmail-find-file nnmbox-active-file))
 237     (setq nnmbox-group-alist (nnmail-get-active))
 238     t))
 239
 240 (deffoo nnmbox-request-newgroups (date &optional server)
 241   (nnmbox-request-list server))
 242
 243 (deffoo nnmbox-request-list-newsgroups (&optional server)
 244   (nnheader-report 'nnmbox "LIST NEWSGROUPS is not implemented."))
 245
 246 (deffoo nnmbox-request-expire-articles
 247     (articles newsgroup &optional server force)
 248   (nnmbox-possibly-change-newsgroup newsgroup server)
 249   (let* ((is-old t)
 250          rest)
 251     (nnmail-activate 'nnmbox)
 252
 253     (with-current-buffer nnmbox-mbox-buffer
 254       (while (and articles is-old)
 255         (when (nnmbox-find-article (car articles))
 256           (if (setq is-old
 257                     (nnmail-expired-article-p
 258                      newsgroup
 259                      (buffer-substring (point) (line-end-position))
 260                      force))
 261               (progn
 262                 (unless (eq nnmail-expiry-target 'delete)
 263                   (with-temp-buffer
 264                     (nnmbox-request-article (car articles)
 265                                             newsgroup server
 266                                             (current-buffer))
 267                     (let ((nnml-current-directory nil))
 268                       (nnmail-expiry-target-group
 269                        nnmail-expiry-target newsgroup)))
 270                   (nnmbox-possibly-change-newsgroup newsgroup server))
 271                 (nnheader-message 5 "Deleting article %d in %s..."
 272                                   (car articles) newsgroup)
 273                 (nnmbox-delete-mail))
 274             (push (car articles) rest)))
 275         (setq articles (cdr articles)))
 276       (nnmbox-save-buffer)
 277       ;; Find the lowest active article in this group.
 278       (let ((active (nth 1 (assoc newsgroup nnmbox-group-alist))))
 279         (while (and (not (nnmbox-find-article (car active)))
 280                     (<= (car active) (cdr active)))
 281           (setcar active (1+ (car active)))))
 282       (nnmbox-save-active nnmbox-group-alist nnmbox-active-file)
 283       (nconc rest articles))))
 284
 285 (deffoo nnmbox-request-move-article
 286     (article group server accept-form &optional last move-is-internal)
 287   (let ((buf (get-buffer-create " *nnmbox move*"))
 288         result)
 289     (and
 290      (nnmbox-request-article article group server)
 291      (with-current-buffer buf
 292        (erase-buffer)
 293        (insert-buffer-substring nntp-server-buffer)
 294        (goto-char (point-min))
 295        (while (re-search-forward
 296                "^X-Gnus-Newsgroup:"
 297                (save-excursion (search-forward "\n\n" nil t) (point)) t)
 298          (gnus-delete-line))
 299        (setq result (eval accept-form))
 300        (kill-buffer buf)
 301        result)
 302      (save-excursion
 303        (nnmbox-possibly-change-newsgroup group server)
 304        (set-buffer nnmbox-mbox-buffer)
 305        (when (nnmbox-find-article article)
 306          (nnmbox-delete-mail))
 307        (and last (nnmbox-save-buffer))))
 308     result))
 309
 310 (deffoo nnmbox-request-accept-article (group &optional server last)
 311   (nnmbox-possibly-change-newsgroup group server)
 312   (nnmail-check-syntax)
 313   (let ((buf (current-buffer))
 314         result cont)
 315     (and
 316      (nnmail-activate 'nnmbox)
 317      (with-temp-buffer
 318        (insert-buffer-substring buf)
 319        (goto-char (point-min))
 320        (cond (;; The From line may have been quoted by movemail.
 321               (looking-at (concat ">" message-unix-mail-delimiter))
 322               (delete-char 1)
 323               (forward-line 1))
 324              ((looking-at "X-From-Line: ")
 325               (replace-match "From ")
 326               (forward-line 1))
 327              (t
 328               (insert "From nobody " (current-time-string) "\n")))
 329        (narrow-to-region (point)
 330                          (if (search-forward "\n\n" nil 'move)
 331                              (1- (point))
 332                            (point)))
 333        (while (re-search-backward "^X-Gnus-Newsgroup: " nil t)
 334          (delete-region (point) (progn (forward-line 1) (point))))
 335        (when nnmail-cache-accepted-message-ids
 336          (nnmail-cache-insert (message-fetch-field "message-id")
 337                               group
 338                               (message-fetch-field "subject")
 339                               (message-fetch-field "from")))
 340        (widen)
 341        (setq result (if (stringp group)
 342                         (list (cons group (nnmbox-active-number group)))
 343                       (nnmail-article-group 'nnmbox-active-number)))
 344        (prog1
 345            (if (and (null result)
 346                     (yes-or-no-p "Moved to `junk' group; delete article? "))
 347                (setq result 'junk)
 348              (setq result (car (nnmbox-save-mail result))))
 349          (setq cont (buffer-string))))
 350      (with-current-buffer nnmbox-mbox-buffer
 351        (goto-char (point-max))
 352        (insert cont)
 353        (when last
 354          (when nnmail-cache-accepted-message-ids
 355            (nnmail-cache-close))
 356          (nnmbox-save-active nnmbox-group-alist nnmbox-active-file)
 357          (nnmbox-save-buffer))))
 358     result))
 359
 360 (deffoo nnmbox-request-replace-article (article group buffer)
 361   (nnmbox-possibly-change-newsgroup group)
 362   (with-current-buffer nnmbox-mbox-buffer
 363     (if (not (nnmbox-find-article article))
 364         nil
 365       (nnmbox-delete-mail t t)
 366       (insert
 367        (with-temp-buffer
 368          (insert-buffer-substring buffer)
 369          (goto-char (point-min))
 370          (when (looking-at "X-From-Line:")
 371            (delete-region (point) (progn (forward-line 1) (point))))
 372          (while (re-search-forward (concat "^" message-unix-mail-delimiter)
 373                                    nil t)
 374            (goto-char (match-beginning 0))
 375            (insert ">"))
 376          (goto-char (point-max))
 377          (unless (bolp)
 378            (insert "\n"))
 379          (buffer-string)))
 380       (nnmbox-save-buffer)
 381       t)))
 382
 383 (deffoo nnmbox-request-delete-group (group &optional force server)
 384   (nnmbox-possibly-change-newsgroup group server)
 385   ;; Delete all articles in GROUP.
 386   (if (not force)
 387       ()                                ; Don't delete the articles.
 388     (with-current-buffer nnmbox-mbox-buffer
 389       (goto-char (point-min))
 390       ;; Delete all articles in this group.
 391       (let ((ident (concat "\nX-Gnus-Newsgroup: " nnmbox-current-group ":"))
 392             found)
 393         (while (search-forward ident nil t)
 394           (setq found t)
 395           (nnmbox-delete-mail))
 396         (when found
 397           (nnmbox-save-buffer)))))
 398   ;; Remove the group from all structures.
 399   (setq nnmbox-group-alist
 400         (delq (assoc group nnmbox-group-alist) nnmbox-group-alist)
 401         nnmbox-current-group nil)
 402   ;; Save the active file.
 403   (nnmbox-save-active nnmbox-group-alist nnmbox-active-file)
 404   t)
 405
 406 (deffoo nnmbox-request-rename-group (group new-name &optional server)
 407   (nnmbox-possibly-change-newsgroup group server)
 408   (with-current-buffer nnmbox-mbox-buffer
 409     (goto-char (point-min))
 410     (let ((ident (concat "\nX-Gnus-Newsgroup: " nnmbox-current-group ":"))
 411           (new-ident (concat "\nX-Gnus-Newsgroup: " new-name ":"))
 412           found)
 413       (while (search-forward ident nil t)
 414         (replace-match new-ident t t)
 415         (setq found t))
 416       (when found
 417         (nnmbox-save-buffer))))
 418   (let ((entry (assoc group nnmbox-group-active-articles)))
 419     (when entry
 420       (setcar entry new-name)))
 421   (let ((entry (assoc group nnmbox-group-alist)))
 422     (when entry
 423       (setcar entry new-name))
 424     (setq nnmbox-current-group nil)
 425     ;; Save the new group alist.
 426     (nnmbox-save-active nnmbox-group-alist nnmbox-active-file)
 427     t))
 428
 429 \f
 430 ;;; Internal functions.
 431
 432 ;; If FORCE, delete article no matter how many X-Gnus-Newsgroup
 433 ;; headers there are.  If LEAVE-DELIM, don't delete the Unix mbox
 434 ;; delimiter line.
 435 (defun nnmbox-delete-mail (&optional force leave-delim)
 436   ;; Delete the current X-Gnus-Newsgroup line.
 437   ;; First delete record of active article, unless the article is being
 438   ;; replaced, indicated by FORCE being non-nil.
 439   (if (not force)
 440       (nnmbox-record-deleted-article (nnmbox-article-group-number t)))
 441   (or force
 442       (gnus-delete-line))
 443   ;; Beginning of the article.
 444   (save-excursion
 445     (save-restriction
 446       (narrow-to-region
 447        (prog2
 448            (re-search-backward (concat "^" message-unix-mail-delimiter) nil t)
 449            (if leave-delim (progn (forward-line 1) (point))
 450              (match-beginning 0))
 451          (forward-line 1))
 452        (or (and (re-search-forward (concat "^" message-unix-mail-delimiter)
 453                                    nil t)
 454                 (match-beginning 0))
 455            (point-max)))
 456       (goto-char (point-min))
 457       ;; Only delete the article if no other group owns it as well.
 458       (when (or force
 459                 (not (re-search-forward "^X-Gnus-Newsgroup: " nil t))
 460                 (search-backward "\n\n" nil t))
 461         (delete-region (point-min) (point-max))))))
 462
 463 (defun nnmbox-possibly-change-newsgroup (newsgroup &optional server)
 464   (when (and server
 465              (not (nnmbox-server-opened server)))
 466     (nnmbox-open-server server))
 467   (when (or (not nnmbox-mbox-buffer)
 468             (not (buffer-name nnmbox-mbox-buffer)))
 469     (nnmbox-read-mbox))
 470   (when (not nnmbox-group-alist)
 471     (nnmail-activate 'nnmbox))
 472   (if newsgroup
 473       (when (assoc newsgroup nnmbox-group-alist)
 474         (setq nnmbox-current-group newsgroup))
 475     t))
 476
 477 (defun nnmbox-article-string (article)
 478   (if (numberp article)
 479       (concat "\nX-Gnus-Newsgroup: " nnmbox-current-group ":"
 480               (int-to-string article) " ")
 481     (concat "\nMessage-ID: " article)))
 482
 483 (defun nnmbox-article-group-number (this-line)
 484   (save-excursion
 485     (if this-line
 486         (beginning-of-line)
 487       (goto-char (point-min)))
 488     (when (re-search-forward "^X-Gnus-Newsgroup: +\\([^:]+\\):\\([0-9]+\\) "
 489                              nil t)
 490       (cons (buffer-substring (match-beginning 1) (match-end 1))
 491             (string-to-number
 492              (buffer-substring (match-beginning 2) (match-end 2)))))))
 493
 494 (defun nnmbox-in-header-p (pos)
 495   "Return non-nil if POS is in the header of an article."
 496   (save-excursion
 497     (goto-char pos)
 498     (re-search-backward (concat "^" message-unix-mail-delimiter) nil t)
 499     (search-forward "\n\n" nil t)
 500     (< pos (point))))
 501
 502 (defun nnmbox-find-article (article)
 503   "Leaves point on the relevant X-Gnus-Newsgroup line if found."
 504   ;; Check that article is in the active range first, to avoid an
 505   ;; expensive exhaustive search if it isn't.
 506   (if (and (numberp article)
 507            (not (nnmbox-is-article-active-p article)))
 508       nil
 509     (let ((art-string (nnmbox-article-string article))
 510           (found nil))
 511       ;; There is the possibility that the X-Gnus-Newsgroup line appears
 512       ;; in the body of an article (for instance, if an article has been
 513       ;; forwarded from someone using Gnus as their mailer), so check
 514       ;; that the line is actually part of the article header.
 515       (or (and (search-forward art-string nil t)
 516                (nnmbox-in-header-p (point)))
 517           (progn
 518             (goto-char (point-min))
 519             (while (and (not found)
 520                         (search-forward art-string nil t))
 521               (setq found (nnmbox-in-header-p (point))))
 522             found)))))
 523
 524 (defun nnmbox-record-active-article (group-art)
 525   (let* ((group (car group-art))
 526          (article (cdr group-art))
 527          (entry
 528           (or (assoc group nnmbox-group-active-articles)
 529               (progn
 530                 (push (list group)
 531                       nnmbox-group-active-articles)
 532                 (car nnmbox-group-active-articles)))))
 533     ;; add article to index, either by building complete list
 534     ;; in reverse order, or as a list of ranges.
 535     (if (not nnmbox-group-building-active-articles)
 536         (setcdr entry (gnus-add-to-range (cdr entry) (list article)))
 537       (when (memq article (cdr entry))
 538         (switch-to-buffer nnmbox-mbox-buffer)
 539         (error "Article %s:%d already exists!" group article))
 540       (when (and (cadr entry) (< article (cadr entry)))
 541         (switch-to-buffer nnmbox-mbox-buffer)
 542         (error "Article %s:%d out of order" group article))
 543       (setcdr entry (cons article (cdr entry))))))
 544
 545 (defun nnmbox-record-deleted-article (group-art)
 546   (let* ((group (car group-art))
 547          (article (cdr group-art))
 548          (entry
 549           (or (assoc group nnmbox-group-active-articles)
 550               (progn
 551                 (push (list group)
 552                       nnmbox-group-active-articles)
 553                 (car nnmbox-group-active-articles)))))
 554     ;; remove article from index
 555     (setcdr entry (gnus-remove-from-range (cdr entry) (list article)))))
 556
 557 (defun nnmbox-is-article-active-p (article)
 558   (gnus-member-of-range
 559    article
 560    (cdr (assoc nnmbox-current-group
 561                nnmbox-group-active-articles))))
 562
 563 (defun nnmbox-save-mail (group-art)
 564   "Called narrowed to an article."
 565   (let ((delim (concat "^" message-unix-mail-delimiter)))
 566     (goto-char (point-min))
 567     ;; This might come from somewhere else.
 568     (if (looking-at delim)
 569         (forward-line 1)
 570       (insert "From nobody " (current-time-string) "\n"))
 571     ;; Quote all "From " lines in the article.
 572     (while (re-search-forward delim nil t)
 573       (goto-char (match-beginning 0))
 574       (insert ">")))
 575   (goto-char (point-max))
 576   (unless (bolp)
 577     (insert "\n"))
 578   (nnmail-insert-lines)
 579   (nnmail-insert-xref group-art)
 580   (nnmbox-insert-newsgroup-line group-art)
 581   (let ((alist group-art))
 582     (while alist
 583       (nnmbox-record-active-article (car alist))
 584       (setq alist (cdr alist))))
 585   (run-hooks 'nnmail-prepare-save-mail-hook)
 586   (run-hooks 'nnmbox-prepare-save-mail-hook)
 587   group-art)
 588
 589 (defun nnmbox-insert-newsgroup-line (group-art)
 590   (save-excursion
 591     (goto-char (point-min))
 592     (when (search-forward "\n\n" nil t)
 593       (forward-char -1)
 594       (while group-art
 595         (insert (format "X-Gnus-Newsgroup: %s:%d   %s\n"
 596                         (caar group-art) (cdar group-art)
 597                         (current-time-string)))
 598         (setq group-art (cdr group-art))))
 599     t))
 600
 601 (defun nnmbox-active-number (group)
 602   ;; Find the next article number in GROUP.
 603   (let ((active (cadr (assoc group nnmbox-group-alist))))
 604     (if active
 605         (setcdr active (1+ (cdr active)))
 606       ;; This group is new, so we create a new entry for it.
 607       ;; This might be a bit naughty... creating groups on the drop of
 608       ;; a hat, but I don't know...
 609       (push (list group (setq active (cons 1 1)))
 610             nnmbox-group-alist))
 611     (cdr active)))
 612
 613 (defun nnmbox-create-mbox ()
 614   (when (not (file-exists-p nnmbox-mbox-file))
 615     (let ((nnmail-file-coding-system
 616            (or nnmbox-file-coding-system-for-write
 617                nnmbox-file-coding-system))
 618           (dir (file-name-directory nnmbox-mbox-file)))
 619       (and dir (gnus-make-directory dir))
 620       (nnmail-write-region (point-min) (point-min)
 621                            nnmbox-mbox-file t 'nomesg))))
 622
 623 (defun nnmbox-read-mbox ()
 624   (nnmail-activate 'nnmbox)
 625   (nnmbox-create-mbox)
 626   (if (and nnmbox-mbox-buffer
 627            (buffer-name nnmbox-mbox-buffer)
 628            (with-current-buffer nnmbox-mbox-buffer
 629              (= (buffer-size) (nnheader-file-size nnmbox-mbox-file))))
 630       ()
 631     (save-excursion
 632       (let ((delim (concat "^" message-unix-mail-delimiter))
 633             (alist nnmbox-group-alist)
 634             (nnmbox-group-building-active-articles t)
 635             start end end-header number)
 636         (set-buffer (setq nnmbox-mbox-buffer
 637                           (let ((nnheader-file-coding-system
 638                                  nnmbox-file-coding-system))
 639                             (nnheader-find-file-noselect
 640                              nnmbox-mbox-file t t))))
 641         (mm-enable-multibyte)
 642         (buffer-disable-undo)
 643         (gnus-add-buffer)
 644
 645         ;; Go through the group alist and compare against the mbox file.
 646         (while alist
 647           (goto-char (point-max))
 648           (when (and (re-search-backward
 649                       (format "^X-Gnus-Newsgroup: %s:\\([0-9]+\\) "
 650                               (caar alist)) nil t)
 651                      (> (setq number
 652                               (string-to-number
 653                                (buffer-substring
 654                                 (match-beginning 1) (match-end 1))))
 655                         (cdadar alist)))
 656             (setcdr (cadar alist) number))
 657           (setq alist (cdr alist)))
 658
 659         ;; Examine all articles for our private X-Gnus-Newsgroup
 660         ;; headers.  This is done primarily as a consistency check, but
 661         ;; it is convenient for building an index of the articles
 662         ;; present, to avoid costly searches for missing articles
 663         ;; (eg. when expiring articles).
 664         (goto-char (point-min))
 665         (setq nnmbox-group-active-articles nil)
 666         (while (re-search-forward delim nil t)
 667           (setq start (match-beginning 0))
 668           (save-excursion
 669             (search-forward "\n\n" nil t)
 670             (setq end-header (point))
 671             (setq end (or (and
 672                            (re-search-forward delim nil t)
 673                            (match-beginning 0))
 674                           (point-max))))
 675           (if (search-forward "\nX-Gnus-Newsgroup: " end-header t)
 676               ;; Build a list of articles in each group, remembering
 677               ;; that each article may be in more than one group.
 678               (progn
 679                 (nnmbox-record-active-article (nnmbox-article-group-number t))
 680                 (while (search-forward "\nX-Gnus-Newsgroup: " end-header t)
 681                   (nnmbox-record-active-article (nnmbox-article-group-number t))))
 682             ;; The article is either new, or for some other reason
 683             ;; hasn't got our private headers, so add them now.  The
 684             ;; only situation I've encountered when the X-Gnus-Newsgroup
 685             ;; header is missing is if the article contains a forwarded
 686             ;; message which does contain that header line (earlier
 687             ;; versions of Gnus didn't restrict their search to the
 688             ;; headers).  In this case, there is an Xref line which
 689             ;; provides the relevant information to construct the
 690             ;; missing header(s).
 691             (save-excursion
 692               (save-restriction
 693                 (narrow-to-region start end)
 694                 (if (re-search-forward "\nXref: [^ ]+" end-header t)
 695                     ;; generate headers from Xref:
 696                     (let (alist)
 697                       (while (re-search-forward " \\([^:]+\\):\\([0-9]+\\)" end-header t)
 698                         (push (cons (match-string 1)
 699                                     (string-to-number (match-string 2))) alist))
 700                       (nnmbox-insert-newsgroup-line alist))
 701                   ;; this is really a new article
 702                   (nnmbox-save-mail
 703                    (nnmail-article-group 'nnmbox-active-number))))))
 704           (goto-char end))
 705         ;; put article lists in order
 706         (setq alist nnmbox-group-active-articles)
 707         (while alist
 708           (setcdr (car alist) (gnus-compress-sequence (nreverse (cdar alist))))
 709           (setq alist (cdr alist)))))))
 710
 711 (provide 'nnmbox)
 712
 713 ;;; nnmbox.el ends here