|
16
|
1 ;;; gnus-async.el --- asynchronous support for Gnus
|
|
|
2 ;; Copyright (C) 1996,97 Free Software Foundation, Inc.
|
|
|
3
|
|
|
4 ;; Author: Lars Magne Ingebrigtsen <larsi@ifi.uio.no>
|
|
|
5 ;; Keywords: news
|
|
|
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 2, or (at your option)
|
|
|
12 ;; 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; see the file COPYING. If not, write to the
|
|
|
21 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
|
22 ;; Boston, MA 02111-1307, USA.
|
|
|
23
|
|
|
24 ;;; Commentary:
|
|
|
25
|
|
|
26 ;;; Code:
|
|
|
27
|
|
|
28 (require 'gnus)
|
|
|
29 (require 'gnus-sum)
|
|
|
30 (require 'nntp)
|
|
|
31
|
|
|
32 (defgroup gnus-asynchronous nil
|
|
|
33 "Support for asynchronous operations."
|
|
|
34 :group 'gnus)
|
|
|
35
|
|
|
36 (defcustom gnus-asynchronous t
|
|
|
37 "*If nil, inhibit all Gnus asynchronicity.
|
|
|
38 If non-nil, let the other asynch variables be heeded."
|
|
|
39 :group 'gnus-asynchronous
|
|
|
40 :type 'boolean)
|
|
|
41
|
|
|
42 (defcustom gnus-use-article-prefetch 30
|
|
|
43 "*If non-nil, prefetch articles in groups that allow this.
|
|
|
44 If a number, prefetch only that many articles forward;
|
|
|
45 if t, prefetch as many articles as possible."
|
|
|
46 :group 'gnus-asynchronous
|
|
|
47 :type '(choice (const :tag "off" nil)
|
|
|
48 (const :tag "all" t)
|
|
|
49 (integer :tag "some" 0)))
|
|
|
50
|
|
|
51 (defcustom gnus-prefetched-article-deletion-strategy '(read exit)
|
|
|
52 "List of symbols that say when to remove articles from the prefetch buffer.
|
|
30
|
53 Possible values in this list are `read', which means that
|
|
16
|
54 articles are removed as they are read, and `exit', which means
|
|
|
55 that all articles belonging to a group are removed on exit
|
|
|
56 from that group."
|
|
|
57 :group 'gnus-asynchronous
|
|
|
58 :type '(set (const read) (const exit)))
|
|
|
59
|
|
|
60 (defcustom gnus-use-header-prefetch nil
|
|
|
61 "*If non-nil, prefetch the headers to the next group."
|
|
|
62 :group 'gnus-asynchronous
|
|
|
63 :type 'boolean)
|
|
|
64
|
|
|
65 (defcustom gnus-async-prefetch-article-p 'gnus-async-unread-p
|
|
|
66 "Function called to say whether an article should be prefetched or not.
|
|
|
67 The function is called with one parameter -- the article data.
|
|
|
68 It should return non-nil if the article is to be prefetched."
|
|
|
69 :group 'gnus-asynchronous
|
|
|
70 :type 'function)
|
|
|
71
|
|
|
72 ;;; Internal variables.
|
|
|
73
|
|
|
74 (defvar gnus-async-prefetch-article-buffer " *Async Prefetch Article*")
|
|
|
75 (defvar gnus-async-article-alist nil)
|
|
|
76 (defvar gnus-async-article-semaphore '(nil))
|
|
|
77 (defvar gnus-async-fetch-list nil)
|
|
|
78
|
|
|
79 (defvar gnus-async-prefetch-headers-buffer " *Async Prefetch Headers*")
|
|
|
80 (defvar gnus-async-header-prefetched nil)
|
|
|
81
|
|
|
82 ;;; Utility functions.
|
|
|
83
|
|
|
84 (defun gnus-group-asynchronous-p (group)
|
|
|
85 "Say whether GROUP is fetched from a server that supports asynchronicity."
|
|
|
86 (gnus-asynchronous-p (gnus-find-method-for-group group)))
|
|
|
87
|
|
|
88 ;;; Somewhat bogus semaphores.
|
|
|
89
|
|
|
90 (defun gnus-async-get-semaphore (semaphore)
|
|
|
91 "Wait until SEMAPHORE is released."
|
|
|
92 (while (/= (length (nconc (symbol-value semaphore) (list nil))) 2)
|
|
|
93 (sleep-for 1)))
|
|
|
94
|
|
|
95 (defun gnus-async-release-semaphore (semaphore)
|
|
|
96 "Release SEMAPHORE."
|
|
|
97 (setcdr (symbol-value semaphore) nil))
|
|
|
98
|
|
|
99 (defmacro gnus-async-with-semaphore (&rest forms)
|
|
|
100 `(unwind-protect
|
|
|
101 (progn
|
|
|
102 (gnus-async-get-semaphore 'gnus-async-article-semaphore)
|
|
|
103 ,@forms)
|
|
|
104 (gnus-async-release-semaphore 'gnus-async-article-semaphore)))
|
|
|
105
|
|
|
106 (put 'gnus-asynch-with-semaphore 'lisp-indent-function 0)
|
|
|
107 (put 'gnus-asynch-with-semaphore 'edebug-form-spec '(body))
|
|
30
|
108
|
|
16
|
109 ;;;
|
|
|
110 ;;; Article prefetch
|
|
|
111 ;;;
|
|
|
112
|
|
|
113 (gnus-add-shutdown 'gnus-async-close 'gnus)
|
|
|
114 (defun gnus-async-close ()
|
|
|
115 (gnus-kill-buffer gnus-async-prefetch-article-buffer)
|
|
|
116 (gnus-kill-buffer gnus-async-prefetch-headers-buffer)
|
|
|
117 (setq gnus-async-article-alist nil
|
|
|
118 gnus-async-header-prefetched nil))
|
|
|
119
|
|
|
120 (defun gnus-async-set-buffer ()
|
|
|
121 (nnheader-set-temp-buffer gnus-async-prefetch-article-buffer t))
|
|
|
122
|
|
|
123 (defun gnus-async-halt-prefetch ()
|
|
|
124 "Stop prefetching."
|
|
|
125 (setq gnus-async-fetch-list nil))
|
|
|
126
|
|
|
127 (defun gnus-async-prefetch-next (group article summary)
|
|
|
128 "Possibly prefetch several articles starting with the article after ARTICLE."
|
|
|
129 (when (and (gnus-buffer-live-p summary)
|
|
|
130 gnus-asynchronous
|
|
|
131 (gnus-group-asynchronous-p group))
|
|
|
132 (save-excursion
|
|
|
133 (set-buffer gnus-summary-buffer)
|
|
|
134 (let ((next (caadr (gnus-data-find-list article))))
|
|
|
135 (when next
|
|
|
136 (if (not (fboundp 'run-with-idle-timer))
|
|
|
137 ;; This is either an older Emacs or XEmacs, so we
|
|
|
138 ;; do this, which leads to slightly slower article
|
|
|
139 ;; buffer display.
|
|
|
140 (gnus-async-prefetch-article group next summary)
|
|
30
|
141 (run-with-idle-timer
|
|
16
|
142 0.1 nil 'gnus-async-prefetch-article group next summary)))))))
|
|
|
143
|
|
|
144 (defun gnus-async-prefetch-article (group article summary &optional next)
|
|
|
145 "Possibly prefetch several articles starting with ARTICLE."
|
|
|
146 (if (not (gnus-buffer-live-p summary))
|
|
|
147 (gnus-async-with-semaphore
|
|
|
148 (setq gnus-async-fetch-list nil))
|
|
|
149 (when (and gnus-asynchronous
|
|
|
150 (gnus-alive-p))
|
|
|
151 (when next
|
|
|
152 (gnus-async-with-semaphore
|
|
|
153 (pop gnus-async-fetch-list)))
|
|
|
154 (let ((do-fetch next)
|
|
|
155 (do-message t)) ;(eq major-mode 'gnus-summary-mode)))
|
|
|
156 (when (and (gnus-group-asynchronous-p group)
|
|
|
157 (gnus-buffer-live-p summary)
|
|
|
158 (or (not next)
|
|
|
159 gnus-async-fetch-list))
|
|
|
160 (gnus-async-with-semaphore
|
|
|
161 (unless next
|
|
|
162 (setq do-fetch (not gnus-async-fetch-list))
|
|
|
163 ;; Nix out any outstanding requests.
|
|
|
164 (setq gnus-async-fetch-list nil)
|
|
|
165 ;; Fill in the new list.
|
|
|
166 (let ((n gnus-use-article-prefetch)
|
|
|
167 (data (gnus-data-find-list article))
|
|
|
168 d)
|
|
|
169 (while (and (setq d (pop data))
|
|
|
170 (if (numberp n)
|
|
|
171 (natnump (decf n))
|
|
|
172 n))
|
|
|
173 (unless (or (gnus-async-prefetched-article-entry
|
|
|
174 group (setq article (gnus-data-number d)))
|
|
|
175 (not (natnump article))
|
|
|
176 (not (funcall gnus-async-prefetch-article-p d)))
|
|
|
177 ;; Not already fetched -- so we add it to the list.
|
|
|
178 (push article gnus-async-fetch-list)))
|
|
|
179 (setq gnus-async-fetch-list
|
|
|
180 (nreverse gnus-async-fetch-list))))
|
|
|
181
|
|
|
182 (when do-fetch
|
|
|
183 (setq article (car gnus-async-fetch-list))))
|
|
30
|
184
|
|
16
|
185 (when (and do-fetch article)
|
|
|
186 ;; We want to fetch some more articles.
|
|
|
187 (save-excursion
|
|
|
188 (set-buffer summary)
|
|
|
189 (let (mark)
|
|
|
190 (gnus-async-set-buffer)
|
|
|
191 (goto-char (point-max))
|
|
|
192 (setq mark (point-marker))
|
|
|
193 (let ((nnheader-callback-function
|
|
30
|
194 (gnus-make-async-article-function
|
|
16
|
195 group article mark summary next))
|
|
30
|
196 (nntp-server-buffer
|
|
16
|
197 (get-buffer gnus-async-prefetch-article-buffer)))
|
|
|
198 (when do-message
|
|
|
199 (gnus-message 7 "Prefetching article %d in group %s"
|
|
|
200 article group))
|
|
|
201 (gnus-request-article article group))))))))))
|
|
|
202
|
|
|
203 (defun gnus-make-async-article-function (group article mark summary next)
|
|
|
204 "Return a callback function."
|
|
|
205 `(lambda (arg)
|
|
|
206 (save-excursion
|
|
|
207 (when arg
|
|
|
208 (gnus-async-set-buffer)
|
|
|
209 (gnus-async-with-semaphore
|
|
|
210 (push (list ',(intern (format "%s-%d" group article))
|
|
|
211 ,mark (set-marker (make-marker) (point-max))
|
|
|
212 ,group ,article)
|
|
|
213 gnus-async-article-alist)))
|
|
|
214 (if (not (gnus-buffer-live-p ,summary))
|
|
|
215 (gnus-async-with-semaphore
|
|
|
216 (setq gnus-async-fetch-list nil))
|
|
|
217 (gnus-async-prefetch-article ,group ,next ,summary t)))))
|
|
|
218
|
|
|
219 (defun gnus-async-unread-p (data)
|
|
|
220 "Return non-nil if DATA represents an unread article."
|
|
|
221 (gnus-data-unread-p data))
|
|
|
222
|
|
|
223 (defun gnus-async-request-fetched-article (group article buffer)
|
|
|
224 "See whether we have ARTICLE from GROUP and put it in BUFFER."
|
|
|
225 (when (numberp article)
|
|
|
226 (let ((entry (gnus-async-prefetched-article-entry group article)))
|
|
|
227 (when entry
|
|
|
228 (save-excursion
|
|
|
229 (gnus-async-set-buffer)
|
|
|
230 (copy-to-buffer buffer (cadr entry) (caddr entry))
|
|
|
231 ;; Remove the read article from the prefetch buffer.
|
|
|
232 (when (memq 'read gnus-prefetched-article-deletion-strategy)
|
|
|
233 (gnus-async-delete-prefected-entry entry))
|
|
|
234 t)))))
|
|
|
235
|
|
|
236 (defun gnus-async-delete-prefected-entry (entry)
|
|
|
237 "Delete ENTRY from buffer and alist."
|
|
|
238 (ignore-errors
|
|
|
239 (delete-region (cadr entry) (caddr entry))
|
|
|
240 (set-marker (cadr entry) nil)
|
|
|
241 (set-marker (caddr entry) nil))
|
|
|
242 (gnus-async-with-semaphore
|
|
30
|
243 (setq gnus-async-article-alist
|
|
16
|
244 (delq entry gnus-async-article-alist))))
|
|
|
245
|
|
|
246 (defun gnus-async-prefetch-remove-group (group)
|
|
|
247 "Remove all articles belonging to GROUP from the prefetch buffer."
|
|
|
248 (when (and (gnus-group-asynchronous-p group)
|
|
|
249 (memq 'exit gnus-prefetched-article-deletion-strategy))
|
|
|
250 (let ((alist gnus-async-article-alist))
|
|
|
251 (save-excursion
|
|
|
252 (gnus-async-set-buffer)
|
|
|
253 (while alist
|
|
|
254 (when (equal group (nth 3 (car alist)))
|
|
|
255 (gnus-async-delete-prefected-entry (car alist)))
|
|
|
256 (pop alist))))))
|
|
30
|
257
|
|
16
|
258 (defun gnus-async-prefetched-article-entry (group article)
|
|
|
259 "Return the entry for ARTICLE in GROUP iff it has been prefetched."
|
|
|
260 (let ((entry (assq (intern (format "%s-%d" group article))
|
|
|
261 gnus-async-article-alist)))
|
|
|
262 ;; Perhaps something has emptied the buffer?
|
|
|
263 (if (and entry
|
|
|
264 (= (cadr entry) (caddr entry)))
|
|
|
265 (progn
|
|
|
266 (ignore-errors
|
|
|
267 (set-marker (cadr entry) nil)
|
|
|
268 (set-marker (caddr entry) nil))
|
|
30
|
269 (setq gnus-async-article-alist
|
|
16
|
270 (delq entry gnus-async-article-alist))
|
|
|
271 nil)
|
|
|
272 entry)))
|
|
|
273
|
|
|
274 ;;;
|
|
|
275 ;;; Header prefetch
|
|
|
276 ;;;
|
|
|
277
|
|
|
278 (defun gnus-async-prefetch-headers (group)
|
|
|
279 "Prefetch the headers for group GROUP."
|
|
|
280 (save-excursion
|
|
|
281 (let (unread)
|
|
|
282 (when (and gnus-use-header-prefetch
|
|
|
283 gnus-asynchronous
|
|
|
284 (gnus-group-asynchronous-p group)
|
|
|
285 (listp gnus-async-header-prefetched)
|
|
|
286 (setq unread (gnus-list-of-unread-articles group)))
|
|
|
287 ;; Mark that a fetch is in progress.
|
|
|
288 (setq gnus-async-header-prefetched t)
|
|
|
289 (nnheader-set-temp-buffer gnus-async-prefetch-headers-buffer t)
|
|
|
290 (erase-buffer)
|
|
|
291 (let ((nntp-server-buffer (current-buffer))
|
|
|
292 (nnheader-callback-function
|
|
|
293 `(lambda (arg)
|
|
|
294 (setq gnus-async-header-prefetched
|
|
|
295 ,(cons group unread)))))
|
|
|
296 (gnus-retrieve-headers unread group gnus-fetch-old-headers))))))
|
|
|
297
|
|
|
298 (defun gnus-async-retrieve-fetched-headers (articles group)
|
|
|
299 "See whether we have prefetched headers."
|
|
|
300 (when (and gnus-use-header-prefetch
|
|
|
301 (gnus-group-asynchronous-p group)
|
|
|
302 (listp gnus-async-header-prefetched)
|
|
|
303 (equal group (car gnus-async-header-prefetched))
|
|
|
304 (equal articles (cdr gnus-async-header-prefetched)))
|
|
|
305 (save-excursion
|
|
|
306 (nnheader-set-temp-buffer gnus-async-prefetch-headers-buffer t)
|
|
|
307 (nntp-decode-text)
|
|
|
308 (copy-to-buffer nntp-server-buffer (point-min) (point-max))
|
|
|
309 (erase-buffer)
|
|
|
310 (setq gnus-async-header-prefetched nil)
|
|
|
311 t)))
|
|
30
|
312
|
|
16
|
313 (provide 'gnus-async)
|
|
|
314
|
|
|
315 ;;; gnus-async.el ends here
|
