lisp/gnus/nnfolder.el

   1 ;;; nnfolder.el --- mail folder access for Gnus
   2 ;; Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000
   3 ;;        Free Software Foundation, Inc.
   4
   5 ;; Author: Scott Byer <byer@mv.us.adobe.com>
   6 ;;      Lars Magne Ingebrigtsen <larsi@gnus.org>
   7 ;;      Masanobu UMEDA <umerin@flab.flab.fujitsu.junet>
   8 ;; Keywords: mail
   9
  10 ;; This file is part of GNU Emacs.
  11
  12 ;; GNU Emacs is free software; you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation; either version 2, or (at your option)
  15 ;; any later version.
  16
  17 ;; GNU Emacs is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  24 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  25 ;; Boston, MA 02111-1307, USA.
  26
  27 ;;; Commentary:
  28
  29 ;;; Code:
  30
  31 (require 'nnheader)
  32 (require 'message)
  33 (require 'nnmail)
  34 (require 'nnoo)
  35 (eval-when-compile (require 'cl))
  36 (require 'gnus-util)
  37
  38 (nnoo-declare nnfolder)
  39
  40 (defvoo nnfolder-directory (expand-file-name message-directory)
  41   "The name of the nnfolder directory.")
  42
  43 (defvoo nnfolder-active-file
  44     (nnheader-concat nnfolder-directory "active")
  45   "The name of the active file.")
  46
  47 ;; I renamed this variable to something more in keeping with the general GNU
  48 ;; style. -SLB
  49
  50 (defvoo nnfolder-ignore-active-file nil
  51   "If non-nil, the active file is ignored.
  52 This causes nnfolder to do some extra work in order to determine the
  53 true active ranges of an mbox file.  Note that the active file is
  54 still saved, but its values are not used.  This costs some extra time
  55 when scanning an mbox when opening it.")
  56
  57 (defvoo nnfolder-distrust-mbox nil
  58   "If non-nil, the folder will be distrusted.
  59 This means that nnfolder will not trust the user with respect to
  60 inserting unaccounted for mail in the middle of an mbox file.  This
  61 can greatly slow down scans, which now must scan the entire file for
  62 unmarked messages.  When nil, scans occur forward from the last marked
  63 message, a huge time saver for large mailboxes.")
  64
  65 (defvoo nnfolder-newsgroups-file
  66     (concat (file-name-as-directory nnfolder-directory) "newsgroups")
  67   "Mail newsgroups description file.")
  68
  69 (defvoo nnfolder-get-new-mail t
  70   "If non-nil, nnfolder will check the incoming mail file and split the mail.")
  71
  72 (defvoo nnfolder-prepare-save-mail-hook nil
  73   "Hook run narrowed to an article before saving.")
  74
  75 (defvoo nnfolder-save-buffer-hook nil
  76   "Hook run before saving the nnfolder mbox buffer.")
  77
  78 (defvoo nnfolder-inhibit-expiry nil
  79   "If non-nil, inhibit expiry.")
  80
  81 \f
  82
  83 (defconst nnfolder-version "nnfolder 1.0"
  84   "nnfolder version.")
  85
  86 (defconst nnfolder-article-marker "X-Gnus-Article-Number: "
  87   "String used to demarcate what the article number for a message is.")
  88
  89 (defvoo nnfolder-current-group nil)
  90 (defvoo nnfolder-current-buffer nil)
  91 (defvoo nnfolder-status-string "")
  92 (defvoo nnfolder-group-alist nil)
  93 (defvoo nnfolder-buffer-alist nil)
  94 (defvoo nnfolder-scantime-alist nil)
  95 (defvoo nnfolder-active-timestamp nil)
  96 (defvoo nnfolder-active-file-coding-system mm-text-coding-system)
  97 (defvoo nnfolder-active-file-coding-system-for-write
  98     nnmail-active-file-coding-system)
  99 (defvoo nnfolder-file-coding-system mm-text-coding-system)
 100 (defvoo nnfolder-file-coding-system-for-write nnheader-file-coding-system
 101   "Coding system for save nnfolder file.
 102 If NIL, NNFOLDER-FILE-CODING-SYSTEM is used.")
 103
 104 \f
 105
 106 ;;; Interface functions
 107
 108 (nnoo-define-basics nnfolder)
 109
 110 (deffoo nnfolder-retrieve-headers (articles &optional group server fetch-old)
 111   (save-excursion
 112     (set-buffer nntp-server-buffer)
 113     (erase-buffer)
 114     (let (article start stop)
 115       (nnfolder-possibly-change-group group server)
 116       (when nnfolder-current-buffer
 117         (set-buffer nnfolder-current-buffer)
 118         (goto-char (point-min))
 119         (if (stringp (car articles))
 120             'headers
 121           (while (setq article (pop articles))
 122             (set-buffer nnfolder-current-buffer)
 123             (when (nnfolder-goto-article article)
 124               (setq start (point))
 125               (setq stop (if (search-forward "\n\n" nil t)
 126                              (1- (point))
 127                            (point-max)))
 128               (set-buffer nntp-server-buffer)
 129               (insert (format "221 %d Article retrieved.\n" article))
 130               (insert-buffer-substring nnfolder-current-buffer start stop)
 131               (goto-char (point-max))
 132               (insert ".\n")))
 133
 134           (set-buffer nntp-server-buffer)
 135           (nnheader-fold-continuation-lines)
 136           'headers)))))
 137
 138 (deffoo nnfolder-open-server (server &optional defs)
 139   (nnoo-change-server 'nnfolder server defs)
 140   (nnmail-activate 'nnfolder t)
 141   (gnus-make-directory nnfolder-directory)
 142   (cond
 143    ((not (file-exists-p nnfolder-directory))
 144     (nnfolder-close-server)
 145     (nnheader-report 'nnfolder "Couldn't create directory: %s"
 146                      nnfolder-directory))
 147    ((not (file-directory-p (file-truename nnfolder-directory)))
 148     (nnfolder-close-server)
 149     (nnheader-report 'nnfolder "Not a directory: %s" nnfolder-directory))
 150    (t
 151     (nnmail-activate 'nnfolder)
 152     (nnheader-report 'nnfolder "Opened server %s using directory %s"
 153                      server nnfolder-directory)
 154     t)))
 155
 156 (deffoo nnfolder-request-close ()
 157   (let ((alist nnfolder-buffer-alist))
 158     (while alist
 159       (nnfolder-close-group (caar alist) nil t)
 160       (setq alist (cdr alist))))
 161   (nnoo-close-server 'nnfolder)
 162   (setq nnfolder-buffer-alist nil
 163         nnfolder-group-alist nil))
 164
 165 (deffoo nnfolder-request-article (article &optional group server buffer)
 166   (nnfolder-possibly-change-group group server)
 167   (save-excursion
 168     (set-buffer nnfolder-current-buffer)
 169     (goto-char (point-min))
 170     (when (nnfolder-goto-article article)
 171       (let (start stop)
 172         (setq start (point))
 173         (forward-line 1)
 174         (unless (and (nnmail-search-unix-mail-delim)
 175                      (forward-line -1))
 176           (goto-char (point-max)))
 177         (setq stop (point))
 178         (let ((nntp-server-buffer (or buffer nntp-server-buffer)))
 179           (set-buffer nntp-server-buffer)
 180           (erase-buffer)
 181           (insert-buffer-substring nnfolder-current-buffer start stop)
 182           (goto-char (point-min))
 183           (while (looking-at "From ")
 184             (delete-char 5)
 185             (insert "X-From-Line: ")
 186             (forward-line 1))
 187           (if (numberp article)
 188               (cons nnfolder-current-group article)
 189             (goto-char (point-min))
 190             (cons nnfolder-current-group
 191                   (if (search-forward (concat "\n" nnfolder-article-marker)
 192                                       nil t)
 193                       (string-to-int
 194                        (buffer-substring
 195                         (point) (progn (end-of-line) (point))))
 196                     -1))))))))
 197
 198 (deffoo nnfolder-request-group (group &optional server dont-check)
 199   (nnfolder-possibly-change-group group server t)
 200   (save-excursion
 201     (if (not (assoc group nnfolder-group-alist))
 202         (nnheader-report 'nnfolder "No such group: %s" group)
 203       (if dont-check
 204           (progn
 205             (nnheader-report 'nnfolder "Selected group %s" group)
 206             t)
 207         (let* ((active (assoc group nnfolder-group-alist))
 208                (group (car active))
 209                (range (cadr active)))
 210           (cond
 211            ((null active)
 212             (nnheader-report 'nnfolder "No such group: %s" group))
 213            ((null nnfolder-current-group)
 214             (nnheader-report 'nnfolder "Empty group: %s" group))
 215            (t
 216             (nnheader-report 'nnfolder "Selected group %s" group)
 217             (nnheader-insert "211 %d %d %d %s\n"
 218                              (1+ (- (cdr range) (car range)))
 219                              (car range) (cdr range) group))))))))
 220
 221 (deffoo nnfolder-request-scan (&optional group server)
 222   (nnfolder-possibly-change-group nil server)
 223   (when nnfolder-get-new-mail
 224     (nnfolder-possibly-change-group group server)
 225     (nnmail-get-new-mail
 226      'nnfolder
 227      (lambda ()
 228        (let ((bufs nnfolder-buffer-alist))
 229          (save-excursion
 230            (while bufs
 231              (if (not (gnus-buffer-live-p (nth 1 (car bufs))))
 232                  (setq nnfolder-buffer-alist
 233                        (delq (car bufs) nnfolder-buffer-alist))
 234                (set-buffer (nth 1 (car bufs)))
 235                (nnfolder-save-buffer)
 236                (kill-buffer (current-buffer)))
 237              (setq bufs (cdr bufs))))))
 238      nnfolder-directory
 239      group)))
 240
 241 ;; Don't close the buffer if we're not shutting down the server.  This way,
 242 ;; we can keep the buffer in the group buffer cache, and not have to grovel
 243 ;; over the buffer again unless we add new mail to it or modify it in some
 244 ;; way.
 245
 246 (deffoo nnfolder-close-group (group &optional server force)
 247   ;; Make sure we _had_ the group open.
 248   (when (or (assoc group nnfolder-buffer-alist)
 249             (equal group nnfolder-current-group))
 250     (let ((inf (assoc group nnfolder-buffer-alist)))
 251       (when inf
 252         (when (and nnfolder-current-group
 253                    nnfolder-current-buffer)
 254           (push (list nnfolder-current-group nnfolder-current-buffer)
 255                 nnfolder-buffer-alist))
 256         (setq nnfolder-buffer-alist
 257               (delq inf nnfolder-buffer-alist))
 258         (setq nnfolder-current-buffer (cadr inf)
 259               nnfolder-current-group (car inf))))
 260     (when (and nnfolder-current-buffer
 261                (buffer-name nnfolder-current-buffer))
 262       (save-excursion
 263         (set-buffer nnfolder-current-buffer)
 264         ;; If the buffer was modified, write the file out now.
 265         (nnfolder-save-buffer)
 266         ;; If we're shutting the server down, we need to kill the
 267         ;; buffer and remove it from the open buffer list.  Or, of
 268         ;; course, if we're trying to minimize our space impact.
 269         (kill-buffer (current-buffer))
 270         (setq nnfolder-buffer-alist (delq (assoc group nnfolder-buffer-alist)
 271                                           nnfolder-buffer-alist)))))
 272   (setq nnfolder-current-group nil
 273         nnfolder-current-buffer nil)
 274   t)
 275
 276 (deffoo nnfolder-request-create-group (group &optional server args)
 277   (nnfolder-possibly-change-group nil server)
 278   (nnmail-activate 'nnfolder)
 279   (when group
 280     (unless (assoc group nnfolder-group-alist)
 281       (push (list group (cons 1 0)) nnfolder-group-alist)
 282       (nnfolder-save-active nnfolder-group-alist nnfolder-active-file)
 283       (nnfolder-read-folder group)))
 284   t)
 285
 286 (deffoo nnfolder-request-list (&optional server)
 287   (nnfolder-possibly-change-group nil server)
 288   (save-excursion
 289     (let ((nnmail-file-coding-system nnfolder-active-file-coding-system))
 290       (nnmail-find-file nnfolder-active-file)
 291       (setq nnfolder-group-alist (nnmail-get-active)))
 292     t))
 293
 294 (deffoo nnfolder-request-newgroups (date &optional server)
 295   (nnfolder-possibly-change-group nil server)
 296   (nnfolder-request-list server))
 297
 298 (deffoo nnfolder-request-list-newsgroups (&optional server)
 299   (nnfolder-possibly-change-group nil server)
 300   (save-excursion
 301     (let ((nnmail-file-coding-system nnfolder-file-coding-system))
 302       (nnmail-find-file nnfolder-newsgroups-file))))
 303
 304 ;; Return a list consisting of all article numbers existing in the
 305 ;; current folder.
 306
 307 (defun nnfolder-existing-articles ()
 308   (save-excursion
 309     (when nnfolder-current-buffer
 310       (set-buffer nnfolder-current-buffer)
 311       (goto-char (point-min))
 312       (let ((marker (concat "\n" nnfolder-article-marker))
 313             (number "[0-9]+")
 314             numbers)
 315
 316         (while (and (search-forward marker nil t)
 317                     (re-search-forward number nil t))
 318           (let ((newnum (string-to-number (match-string 0))))
 319             (if (nnmail-within-headers-p)
 320                 (push newnum numbers))))
 321         numbers))))
 322
 323 (deffoo nnfolder-request-expire-articles
 324     (articles newsgroup &optional server force)
 325   (nnfolder-possibly-change-group newsgroup server)
 326   (let* ((is-old t)
 327          ;; The articles we have deleted so far.
 328          (deleted-articles nil)
 329          ;; The articles that really exist and will
 330          ;; be expired if they are old enough.
 331          (maybe-expirable
 332           (gnus-intersection articles (nnfolder-existing-articles))))
 333     (nnmail-activate 'nnfolder)
 334
 335     (save-excursion
 336       (set-buffer nnfolder-current-buffer)
 337       ;; Since messages are sorted in arrival order and expired in the
 338       ;; same order, we can stop as soon as we find a message that is
 339       ;; too old.
 340       (while (and maybe-expirable is-old)
 341         (goto-char (point-min))
 342         (when (and (nnfolder-goto-article (car maybe-expirable))
 343                    (search-forward (concat "\n" nnfolder-article-marker)
 344                                    nil t))
 345           (forward-sexp)
 346           (when (setq is-old
 347                       (nnmail-expired-article-p
 348                        newsgroup
 349                        (buffer-substring
 350                         (point) (progn (end-of-line) (point)))
 351                        force nnfolder-inhibit-expiry))
 352             (nnheader-message 5 "Deleting article %d..."
 353                               (car maybe-expirable) newsgroup)
 354             (nnfolder-delete-mail)
 355             ;; Must remember which articles were actually deleted
 356             (push (car maybe-expirable) deleted-articles)))
 357         (setq maybe-expirable (cdr maybe-expirable)))
 358       (unless nnfolder-inhibit-expiry
 359         (nnheader-message 5 "Deleting articles...done"))
 360       (nnfolder-save-buffer)
 361       (nnfolder-adjust-min-active newsgroup)
 362       (nnfolder-save-active nnfolder-group-alist nnfolder-active-file)
 363       (gnus-sorted-complement articles (nreverse deleted-articles)))))
 364
 365 (deffoo nnfolder-request-move-article (article group server
 366                                                accept-form &optional last)
 367   (save-excursion
 368     (let ((buf (get-buffer-create " *nnfolder move*"))
 369           result)
 370       (and
 371        (nnfolder-request-article article group server)
 372        (save-excursion
 373          (set-buffer buf)
 374          (erase-buffer)
 375          (insert-buffer-substring nntp-server-buffer)
 376          (goto-char (point-min))
 377          (while (re-search-forward
 378                  (concat "^" nnfolder-article-marker)
 379                  (save-excursion (and (search-forward "\n\n" nil t) (point)))
 380                  t)
 381            (delete-region (progn (beginning-of-line) (point))
 382                           (progn (forward-line 1) (point))))
 383          (setq result (eval accept-form))
 384          (kill-buffer buf)
 385          result)
 386        (save-excursion
 387          (nnfolder-possibly-change-group group server)
 388          (set-buffer nnfolder-current-buffer)
 389          (goto-char (point-min))
 390          (when (nnfolder-goto-article article)
 391            (nnfolder-delete-mail))
 392          (when last
 393            (nnfolder-save-buffer)
 394            (nnfolder-adjust-min-active group)
 395            (nnfolder-save-active nnfolder-group-alist nnfolder-active-file))))
 396       result)))
 397
 398 (deffoo nnfolder-request-accept-article (group &optional server last)
 399   (save-excursion
 400     (nnfolder-possibly-change-group group server)
 401     (nnmail-check-syntax)
 402     (let ((buf (current-buffer))
 403           result art-group)
 404       (goto-char (point-min))
 405       (when (looking-at "X-From-Line: ")
 406         (replace-match "From "))
 407       (and
 408        (nnfolder-request-list)
 409        (save-excursion
 410          (set-buffer buf)
 411          (goto-char (point-min))
 412          (if (search-forward "\n\n" nil t)
 413              (forward-line -1)
 414            (goto-char (point-max)))
 415          (while (re-search-backward (concat "^" nnfolder-article-marker) nil t)
 416            (delete-region (point) (progn (forward-line 1) (point))))
 417          (when nnmail-cache-accepted-message-ids
 418            (nnmail-cache-insert (nnmail-fetch-field "message-id")))
 419          (setq result (if (stringp group)
 420                           (list (cons group (nnfolder-active-number group)))
 421                         (setq art-group
 422                               (nnmail-article-group 'nnfolder-active-number))))
 423          (if (and (null result)
 424                   (yes-or-no-p "Moved to `junk' group; delete article? "))
 425              (setq result 'junk)
 426            (setq result
 427                  (car (nnfolder-save-mail result)))))
 428        (when last
 429          (save-excursion
 430            (nnfolder-possibly-change-folder (or (caar art-group) group))
 431            (nnfolder-save-buffer)
 432            (when nnmail-cache-accepted-message-ids
 433              (nnmail-cache-close)))))
 434       (nnfolder-save-active nnfolder-group-alist nnfolder-active-file)
 435       (unless result
 436         (nnheader-report 'nnfolder "Couldn't store article"))
 437       result)))
 438
 439 (deffoo nnfolder-request-replace-article (article group buffer)
 440   (nnfolder-possibly-change-group group)
 441   (save-excursion
 442     (set-buffer buffer)
 443     (goto-char (point-min))
 444     (let (xfrom)
 445       (while (re-search-forward "^X-From-Line: \\(.*\\)$" nil t)
 446         (setq xfrom (match-string 1))
 447         (gnus-delete-line))
 448       (goto-char (point-min))
 449       (if xfrom
 450           (insert "From " xfrom "\n")
 451         (unless (looking-at "From ")
 452           (insert "From nobody " (current-time-string) "\n"))))
 453     (nnfolder-normalize-buffer)
 454     (set-buffer nnfolder-current-buffer)
 455     (goto-char (point-min))
 456     (if (not (nnfolder-goto-article article))
 457         nil
 458       (nnfolder-delete-mail)
 459       (insert-buffer-substring buffer)
 460       (nnfolder-save-buffer)
 461       t)))
 462
 463 (deffoo nnfolder-request-delete-group (group &optional force server)
 464   (nnfolder-close-group group server t)
 465   ;; Delete all articles in GROUP.
 466   (if (not force)
 467       ()                                ; Don't delete the articles.
 468     ;; Delete the file that holds the group.
 469     (ignore-errors
 470       (delete-file (nnfolder-group-pathname group))))
 471   ;; Remove the group from all structures.
 472   (setq nnfolder-group-alist
 473         (delq (assoc group nnfolder-group-alist) nnfolder-group-alist)
 474         nnfolder-current-group nil
 475         nnfolder-current-buffer nil)
 476   ;; Save the active file.
 477   (nnfolder-save-active nnfolder-group-alist nnfolder-active-file)
 478   t)
 479
 480 (deffoo nnfolder-request-rename-group (group new-name &optional server)
 481   (nnfolder-possibly-change-group group server)
 482   (save-excursion
 483     (set-buffer nnfolder-current-buffer)
 484     (and (file-writable-p buffer-file-name)
 485          (ignore-errors
 486            (rename-file
 487             buffer-file-name
 488             (let ((new-file (nnfolder-group-pathname new-name)))
 489               (gnus-make-directory (file-name-directory new-file))
 490               new-file))
 491            t)
 492          ;; That went ok, so we change the internal structures.
 493          (let ((entry (assoc group nnfolder-group-alist)))
 494            (and entry (setcar entry new-name))
 495            (setq nnfolder-current-buffer nil
 496                  nnfolder-current-group nil)
 497            ;; Save the new group alist.
 498            (nnfolder-save-active nnfolder-group-alist nnfolder-active-file)
 499            ;; We kill the buffer instead of renaming it and stuff.
 500            (kill-buffer (current-buffer))
 501            t))))
 502
 503 (defun nnfolder-request-regenerate (server)
 504   (nnfolder-possibly-change-group nil server)
 505   (nnfolder-generate-active-file)
 506   t)
 507
 508 \f
 509 ;;; Internal functions.
 510
 511 (defun nnfolder-adjust-min-active (group)
 512   ;; Find the lowest active article in this group.
 513   (let* ((active (cadr (assoc group nnfolder-group-alist)))
 514          (marker (concat "\n" nnfolder-article-marker))
 515          (number "[0-9]+")
 516          (activemin (cdr active)))
 517     (save-excursion
 518       (set-buffer nnfolder-current-buffer)
 519       (goto-char (point-min))
 520       (while (and (search-forward marker nil t)
 521                   (re-search-forward number nil t))
 522         (let ((newnum (string-to-number (match-string 0))))
 523           (if (nnmail-within-headers-p)
 524               (setq activemin (min activemin newnum)))))
 525       (setcar active activemin))))
 526
 527 (defun nnfolder-article-string (article)
 528   (if (numberp article)
 529       (concat "\n" nnfolder-article-marker (int-to-string article) " ")
 530     (concat "\nMessage-ID: " article)))
 531
 532 (defun nnfolder-goto-article (article)
 533   "Place point at the start of the headers of ARTICLE.
 534 ARTICLE can be an article number or a Message-ID.
 535 Returns t if successful, nil otherwise."
 536   (let ((art-string (nnfolder-article-string article))
 537         start found)
 538     ;; It is likely that we are at or before the delimiter line.
 539     ;; We therefore go to the end of the previous line, and start
 540     ;; searching from there.
 541     (beginning-of-line)
 542     (unless (bobp)
 543       (forward-char -1))
 544     (setq start (point))
 545     ;; First search forward.
 546     (while (and (setq found (search-forward art-string nil t))
 547                 (not (nnmail-within-headers-p))))
 548     ;; If unsuccessful, search backward from where we started,
 549     (unless found
 550       (goto-char start)
 551       (while (and (setq found (search-backward art-string nil t))
 552                   (not (nnmail-within-headers-p)))))
 553     (when found
 554       (nnmail-search-unix-mail-delim-backward))))
 555
 556 (defun nnfolder-delete-mail (&optional leave-delim)
 557   "Delete the message that point is in.
 558 If optional argument LEAVE-DELIM is t, then mailbox delimiter is not
 559 deleted.  Point is left where the deleted region was."
 560   (save-restriction
 561     (narrow-to-region
 562      (save-excursion
 563        ;; In case point is at the beginning of the message already.
 564        (forward-line 1)
 565        (nnmail-search-unix-mail-delim-backward)
 566        (if leave-delim (progn (forward-line 1) (point))
 567          (point)))
 568      (progn
 569        (forward-line 1)
 570        (if (nnmail-search-unix-mail-delim)
 571            (point)
 572          (point-max))))
 573     (run-hooks 'nnfolder-delete-mail-hook)
 574     (delete-region (point-min) (point-max))))
 575
 576 (defun nnfolder-possibly-change-group (group &optional server dont-check)
 577   ;; Change servers.
 578   (when (and server
 579              (not (nnfolder-server-opened server)))
 580     (nnfolder-open-server server))
 581   (unless (gnus-buffer-live-p nnfolder-current-buffer)
 582     (setq nnfolder-current-buffer nil
 583           nnfolder-current-group nil))
 584   ;; Change group.
 585   (when (and group
 586              (not (equal group nnfolder-current-group)))
 587     (let ((file-name-coding-system nnmail-pathname-coding-system))
 588       (nnmail-activate 'nnfolder)
 589       (when (and (not (assoc group nnfolder-group-alist))
 590                  (not (file-exists-p
 591                        (nnfolder-group-pathname group))))
 592         ;; The group doesn't exist, so we create a new entry for it.
 593         (push (list group (cons 1 0)) nnfolder-group-alist)
 594         (nnfolder-save-active nnfolder-group-alist nnfolder-active-file))
 595
 596       (if dont-check
 597           (setq nnfolder-current-group group
 598                 nnfolder-current-buffer nil)
 599         (let (inf file)
 600           ;; If we have to change groups, see if we don't already have the
 601           ;; folder in memory.  If we do, verify the modtime and destroy
 602           ;; the folder if needed so we can rescan it.
 603           (setq nnfolder-current-buffer
 604                 (nth 1 (assoc group nnfolder-buffer-alist)))
 605
 606           ;; If the buffer is not live, make sure it isn't in the alist.  If it
 607           ;; is live, verify that nobody else has touched the file since last
 608           ;; time.
 609           (when (and nnfolder-current-buffer
 610                      (not (gnus-buffer-live-p nnfolder-current-buffer)))
 611             (setq nnfolder-buffer-alist (delq inf nnfolder-buffer-alist)
 612                   nnfolder-current-buffer nil))
 613
 614           (setq nnfolder-current-group group)
 615
 616           (when (or (not nnfolder-current-buffer)
 617                     (not (verify-visited-file-modtime
 618                           nnfolder-current-buffer)))
 619             (save-excursion
 620               (setq file (nnfolder-group-pathname group))
 621               ;; See whether we need to create the new file.
 622               (unless (file-exists-p file)
 623                 (gnus-make-directory (file-name-directory file))
 624                 (let ((nnmail-file-coding-system
 625                        (or nnfolder-file-coding-system-for-write
 626                            nnfolder-file-coding-system-for-write)))
 627                   (nnmail-write-region 1 1 file t 'nomesg)))
 628               (when (setq nnfolder-current-buffer (nnfolder-read-folder group))
 629                 (set-buffer nnfolder-current-buffer)
 630                 (push (list group nnfolder-current-buffer)
 631                       nnfolder-buffer-alist)))))))))
 632
 633 (defun nnfolder-save-mail (group-art-list)
 634   "Called narrowed to an article."
 635   (let* (save-list group-art)
 636     (goto-char (point-min))
 637     ;; The From line may have been quoted by movemail.
 638     (when (looking-at ">From")
 639       (delete-char 1))
 640     ;; This might come from somewhere else.
 641     (unless (looking-at "From ")
 642       (insert "From nobody " (current-time-string) "\n")
 643       (goto-char (point-min)))
 644     ;; Quote all "From " lines in the article.
 645     (forward-line 1)
 646     (let (case-fold-search)
 647       (while (re-search-forward "^From " nil t)
 648         (beginning-of-line)
 649         (insert "> ")))
 650     (setq save-list group-art-list)
 651     (nnmail-insert-lines)
 652     (nnmail-insert-xref group-art-list)
 653     (run-hooks 'nnmail-prepare-save-mail-hook)
 654     (run-hooks 'nnfolder-prepare-save-mail-hook)
 655
 656     ;; Insert the mail into each of the destination groups.
 657     (while (setq group-art (pop group-art-list))
 658       ;; Kill any previous newsgroup markers.
 659       (goto-char (point-min))
 660       (if (search-forward "\n\n" nil t)
 661           (forward-line -1)
 662         (goto-char (point-max)))
 663       (while (search-backward (concat "\n" nnfolder-article-marker) nil t)
 664         (delete-region (1+ (point)) (progn (forward-line 2) (point))))
 665
 666       ;; Insert the new newsgroup marker.
 667       (nnfolder-insert-newsgroup-line group-art)
 668
 669       (save-excursion
 670         (let ((beg (point-min))
 671               (end (point-max))
 672               (obuf (current-buffer)))
 673           (nnfolder-possibly-change-folder (car group-art))
 674           (let ((buffer-read-only nil))
 675             (nnfolder-normalize-buffer)
 676             (insert-buffer-substring obuf beg end)))))
 677
 678     ;; Did we save it anywhere?
 679     save-list))
 680
 681 (defun nnfolder-normalize-buffer ()
 682   "Make sure there are two newlines at the end of the buffer."
 683   (goto-char (point-max))
 684   (skip-chars-backward "\n")
 685   (delete-region (point) (point-max))
 686   (insert "\n\n"))
 687
 688 (defun nnfolder-insert-newsgroup-line (group-art)
 689   (save-excursion
 690     (goto-char (point-min))
 691     (unless (search-forward "\n\n" nil t)
 692       (goto-char (point-max))
 693       (insert "\n"))
 694     (forward-char -1)
 695     (insert (format (concat nnfolder-article-marker "%d   %s\n")
 696                     (cdr group-art) (current-time-string)))))
 697
 698 (defun nnfolder-active-number (group)
 699   ;; Find the next article number in GROUP.
 700   (let ((active (cadr (assoc group nnfolder-group-alist))))
 701     (if active
 702         (setcdr active (1+ (cdr active)))
 703       ;; This group is new, so we create a new entry for it.
 704       ;; This might be a bit naughty... creating groups on the drop of
 705       ;; a hat, but I don't know...
 706       (push (list group (setq active (cons 1 1)))
 707             nnfolder-group-alist))
 708     (cdr active)))
 709
 710 (defun nnfolder-possibly-change-folder (group)
 711   (let ((inf (assoc group nnfolder-buffer-alist)))
 712     (if (and inf
 713              (gnus-buffer-live-p (cadr inf)))
 714         (set-buffer (cadr inf))
 715       (when inf
 716         (setq nnfolder-buffer-alist (delq inf nnfolder-buffer-alist)))
 717       (when nnfolder-group-alist
 718         (nnfolder-save-active nnfolder-group-alist nnfolder-active-file))
 719       (push (list group (nnfolder-read-folder group))
 720             nnfolder-buffer-alist))))
 721
 722 ;; This method has a problem if you've accidentally let the active list get
 723 ;; out of sync with the files.  This could happen, say, if you've
 724 ;; accidentally gotten new mail with something other than Gnus (but why
 725 ;; would _that_ ever happen? :-).  In that case, we will be in the middle of
 726 ;; processing the file, ready to add new X-Gnus article number markers, and
 727 ;; we'll run across a message with no ID yet - the active list _may_not_ be
 728 ;; ready for us yet.
 729
 730 ;; To handle this, I'm modifying this routine to maintain the maximum ID seen
 731 ;; so far, and when we hit a message with no ID, we will _manually_ scan the
 732 ;; rest of the message looking for any more, possibly higher IDs.  We'll
 733 ;; assume the maximum that we find is the highest active.  Note that this
 734 ;; shouldn't cost us much extra time at all, but will be a lot less
 735 ;; vulnerable to glitches between the mbox and the active file.
 736
 737 (defun nnfolder-read-folder (group)
 738   (let* ((file (nnfolder-group-pathname group))
 739          (buffer (set-buffer
 740                   (let ((nnheader-file-coding-system
 741                          nnfolder-file-coding-system))
 742                     (nnheader-find-file-noselect file)))))
 743     (if (equal (cadr (assoc group nnfolder-scantime-alist))
 744                (nth 5 (file-attributes file)))
 745         ;; This looks up-to-date, so we don't do any scanning.
 746         (if (file-exists-p file)
 747             buffer
 748           (push (list group buffer) nnfolder-buffer-alist)
 749           (set-buffer-modified-p t)
 750           (nnfolder-save-buffer))
 751       ;; Parse the damn thing.
 752       (save-excursion
 753         (goto-char (point-min))
 754         ;; Remove any blank lines at the start.
 755         (while (eq (following-char) ?\n)
 756           (delete-char 1))
 757         (nnmail-activate 'nnfolder)
 758         ;; Read in the file.
 759         (let ((delim "^From ")
 760               (marker (concat "\n" nnfolder-article-marker))
 761               (number "[0-9]+")
 762               (active (or (cadr (assoc group nnfolder-group-alist))
 763                           (cons 1 0)))
 764               (scantime (assoc group nnfolder-scantime-alist))
 765               (minid (lsh -1 -1))
 766               maxid start end newscantime
 767               buffer-read-only)
 768           (buffer-disable-undo)
 769           (setq maxid (cdr active))
 770           (goto-char (point-min))
 771
 772           ;; Anytime the active number is 1 or 0, it is suspect.  In that
 773           ;; case, search the file manually to find the active number.  Or,
 774           ;; of course, if we're being paranoid.  (This would also be the
 775           ;; place to build other lists from the header markers, such as
 776           ;; expunge lists, etc., if we ever desired to abandon the active
 777           ;; file entirely for mboxes.)
 778           (when (or nnfolder-ignore-active-file
 779                     (< maxid 2))
 780             (while (and (search-forward marker nil t)
 781                         (re-search-forward number nil t))
 782               (let ((newnum (string-to-number (match-string 0))))
 783                 (if (nnmail-within-headers-p)
 784                     (setq maxid (max maxid newnum)
 785                           minid (min minid newnum)))))
 786             (setcar active (max 1 (min minid maxid)))
 787             (setcdr active (max maxid (cdr active)))
 788             (goto-char (point-min)))
 789
 790           ;; As long as we trust that the user will only insert unmarked mail
 791           ;; at the end, go to the end and search backwards for the last
 792           ;; marker.  Find the start of that message, and begin to search for
 793           ;; unmarked messages from there.
 794           (when (not (or nnfolder-distrust-mbox
 795                          (< maxid 2)))
 796             (goto-char (point-max))
 797             (unless (re-search-backward marker nil t)
 798               (goto-char (point-min)))
 799             (when (nnmail-search-unix-mail-delim)
 800               (goto-char (point-min))))
 801
 802           ;; Keep track of the active number on our own, and insert it back
 803           ;; into the active list when we're done.  Also, prime the pump to
 804           ;; cut down on the number of searches we do.
 805           (unless (nnmail-search-unix-mail-delim)
 806             (goto-char (point-max)))
 807           (setq end (point-marker))
 808           (while (not (= end (point-max)))
 809             (setq start (marker-position end))
 810             (goto-char end)
 811             ;; There may be more than one "From " line, so we skip past
 812             ;; them.
 813             (while (looking-at delim)
 814               (forward-line 1))
 815             (set-marker end (if (nnmail-search-unix-mail-delim)
 816                                 (point)
 817                               (point-max)))
 818             (goto-char start)
 819             (when (not (search-forward marker end t))
 820               (narrow-to-region start end)
 821               (nnmail-insert-lines)
 822               (nnfolder-insert-newsgroup-line
 823                (cons nil (nnfolder-active-number nnfolder-current-group)))
 824               (widen)))
 825
 826           (set-marker end nil)
 827           ;; Make absolutely sure that the active list reflects reality!
 828           (nnfolder-save-active nnfolder-group-alist nnfolder-active-file)
 829           ;; Set the scantime for this group.
 830           (setq newscantime (visited-file-modtime))
 831           (if scantime
 832               (setcdr scantime (list newscantime))
 833             (push (list nnfolder-current-group newscantime)
 834                   nnfolder-scantime-alist))
 835           (current-buffer))))))
 836
 837 ;;;###autoload
 838 (defun nnfolder-generate-active-file ()
 839   "Look for mbox folders in the nnfolder directory and make them into groups.
 840 This command does not work if you use short group names."
 841   (interactive)
 842   (nnmail-activate 'nnfolder)
 843   (let ((files (directory-files nnfolder-directory))
 844         file)
 845     (while (setq file (pop files))
 846       (when (and (not (backup-file-name-p file))
 847                  (message-mail-file-mbox-p
 848                   (nnheader-concat nnfolder-directory file)))
 849         (let ((oldgroup (assoc file nnfolder-group-alist)))
 850           (if oldgroup
 851               (nnheader-message 5 "Refreshing group %s..." file)
 852             (nnheader-message 5 "Adding group %s..." file))
 853           (if oldgroup
 854               (setq nnfolder-group-alist
 855                     (delq oldgroup (copy-sequence nnfolder-group-alist))))
 856           (push (list file (cons 1 0)) nnfolder-group-alist)
 857           (nnfolder-possibly-change-folder file)
 858           (nnfolder-possibly-change-group file)
 859           (nnfolder-close-group file))))
 860     (nnheader-message 5 "")))
 861
 862 (defun nnfolder-group-pathname (group)
 863   "Make pathname for GROUP."
 864   (setq group
 865         (mm-encode-coding-string group nnmail-pathname-coding-system))
 866   (let ((dir (file-name-as-directory (expand-file-name nnfolder-directory))))
 867     ;; If this file exists, we use it directly.
 868     (if (or nnmail-use-long-file-names
 869             (file-exists-p (concat dir group)))
 870         (concat dir group)
 871       ;; If not, we translate dots into slashes.
 872       (concat dir (nnheader-replace-chars-in-string group ?. ?/)))))
 873
 874 (defun nnfolder-save-buffer ()
 875   "Save the buffer."
 876   (when (buffer-modified-p)
 877     (run-hooks 'nnfolder-save-buffer-hook)
 878     (gnus-make-directory (file-name-directory (buffer-file-name)))
 879     (let ((coding-system-for-write
 880            (or nnfolder-file-coding-system-for-write
 881                nnfolder-file-coding-system)))
 882       (save-buffer))))
 883
 884 (defun nnfolder-save-active (group-alist active-file)
 885   (let ((nnmail-active-file-coding-system
 886          (or nnfolder-active-file-coding-system-for-write
 887              nnfolder-active-file-coding-system)))
 888     (nnmail-save-active group-alist active-file)))
 889
 890 (provide 'nnfolder)
 891
 892 ;;; nnfolder.el ends here