;;; gnus-async.el --- asynchronous support for Gnus
-;; Copyright (C) 1996 Free Software Foundation, Inc.
+;; Copyright (C) 1996,97 Free Software Foundation, Inc.
;; Author: Lars Magne Ingebrigtsen <larsi@ifi.uio.no>
;; Keywords: news
;;; Code:
-(require 'gnus-load)
+(require 'gnus)
(require 'gnus-sum)
(require 'nntp)
-(defvar gnus-asynchronous t
+(defgroup gnus-asynchronous nil
+ "Support for asynchronous operations."
+ :group 'gnus)
+
+(defcustom gnus-asynchronous t
"*If nil, inhibit all Gnus asynchronicity.
-If non-nil, let the other asynch variables be heeded.")
+If non-nil, let the other asynch variables be heeded."
+ :group 'gnus-asynchronous
+ :type 'boolean)
-(defvar gnus-use-article-prefetch 30
+(defcustom gnus-use-article-prefetch 30
"*If non-nil, prefetch articles in groups that allow this.
If a number, prefetch only that many articles forward;
-if t, prefetch as many articles as possible.")
+if t, prefetch as many articles as possible."
+ :group 'gnus-asynchronous
+ :type '(choice (const :tag "off" nil)
+ (const :tag "all" t)
+ (integer :tag "some" 0)))
-(defvar gnus-prefetched-article-deletion-strategy '(read exit)
+(defcustom gnus-prefetched-article-deletion-strategy '(read exit)
"List of symbols that say when to remove articles from the prefetch buffer.
-Possible values in this list are `read', which means that
+Possible values in this list are `read', which means that
articles are removed as they are read, and `exit', which means
that all articles belonging to a group are removed on exit
-from that group.")
-
-(defvar gnus-use-header-prefetch nil
- "*If non-nil, prefetch the headers to the next group.")
+from that group."
+ :group 'gnus-asynchronous
+ :type '(set (const read) (const exit)))
+
+(defcustom gnus-use-header-prefetch nil
+ "*If non-nil, prefetch the headers to the next group."
+ :group 'gnus-asynchronous
+ :type 'boolean)
+
+(defcustom gnus-async-prefetch-article-p 'gnus-async-unread-p
+ "Function called to say whether an article should be prefetched or not.
+The function is called with one parameter -- the article data.
+It should return non-nil if the article is to be prefetched."
+ :group 'gnus-asynchronous
+ :type 'function)
;;; Internal variables.
;;; Utility functions.
(defun gnus-group-asynchronous-p (group)
- "Say whether GROUP is fetched from a server that supports asynchronocity."
+ "Say whether GROUP is fetched from a server that supports asynchronicity."
(gnus-asynchronous-p (gnus-find-method-for-group group)))
;;; Somewhat bogus semaphores.
"Release SEMAPHORE."
(setcdr (symbol-value semaphore) nil))
+(defmacro gnus-async-with-semaphore (&rest forms)
+ `(unwind-protect
+ (progn
+ (gnus-async-get-semaphore 'gnus-async-article-semaphore)
+ ,@forms)
+ (gnus-async-release-semaphore 'gnus-async-article-semaphore)))
+
+(put 'gnus-asynch-with-semaphore 'lisp-indent-function 0)
+(put 'gnus-asynch-with-semaphore 'edebug-form-spec '(body))
+
;;;
;;; Article prefetch
;;;
(defun gnus-async-set-buffer ()
(nnheader-set-temp-buffer gnus-async-prefetch-article-buffer t))
+(defun gnus-async-halt-prefetch ()
+ "Stop prefetching."
+ (setq gnus-async-fetch-list nil))
+
(defun gnus-async-prefetch-next (group article summary)
"Possibly prefetch several articles starting with the article after ARTICLE."
(when (and (gnus-buffer-live-p summary)
;; do this, which leads to slightly slower article
;; buffer display.
(gnus-async-prefetch-article group next summary)
- (run-with-idle-timer
+ (run-with-idle-timer
0.1 nil 'gnus-async-prefetch-article group next summary)))))))
(defun gnus-async-prefetch-article (group article summary &optional next)
"Possibly prefetch several articles starting with ARTICLE."
(if (not (gnus-buffer-live-p summary))
- (progn
- (gnus-async-get-semaphore 'gnus-async-article-semaphore)
- (setq gnus-async-fetch-list nil)
- (gnus-async-release-semaphore 'gnus-async-article-semaphore))
+ (gnus-async-with-semaphore
+ (setq gnus-async-fetch-list nil))
(when (and gnus-asynchronous
(gnus-alive-p))
(when next
- (gnus-async-get-semaphore 'gnus-async-article-semaphore)
- (pop gnus-async-fetch-list)
- (gnus-async-release-semaphore 'gnus-async-article-semaphore))
- (let ((do-fetch next))
+ (gnus-async-with-semaphore
+ (pop gnus-async-fetch-list)))
+ (let ((do-fetch next)
+ (do-message t)) ;(eq major-mode 'gnus-summary-mode)))
(when (and (gnus-group-asynchronous-p group)
(gnus-buffer-live-p summary)
(or (not next)
gnus-async-fetch-list))
- (unwind-protect
- (progn
- (gnus-async-get-semaphore 'gnus-async-article-semaphore)
- (unless next
- (setq do-fetch (not gnus-async-fetch-list))
- ;; Nix out any outstanding requests.
- (setq gnus-async-fetch-list nil)
- ;; Fill in the new list.
- (let ((n gnus-use-article-prefetch)
- (data (gnus-data-find-list article))
- d)
- (while (and (setq d (pop data))
- (if (numberp n)
- (natnump (decf n))
- n))
- (unless (or (gnus-async-prefetched-article-entry
- group (setq article (gnus-data-number d)))
- (not (natnump article)))
- ;; Not already fetched -- so we add it to the list.
- (push article gnus-async-fetch-list)))
- (setq gnus-async-fetch-list
- (nreverse gnus-async-fetch-list))))
-
- (when do-fetch
- (setq article (car gnus-async-fetch-list))))
-
- (gnus-async-release-semaphore 'gnus-async-article-semaphore))
-
+ (gnus-async-with-semaphore
+ (unless next
+ (setq do-fetch (not gnus-async-fetch-list))
+ ;; Nix out any outstanding requests.
+ (setq gnus-async-fetch-list nil)
+ ;; Fill in the new list.
+ (let ((n gnus-use-article-prefetch)
+ (data (gnus-data-find-list article))
+ d)
+ (while (and (setq d (pop data))
+ (if (numberp n)
+ (natnump (decf n))
+ n))
+ (unless (or (gnus-async-prefetched-article-entry
+ group (setq article (gnus-data-number d)))
+ (not (natnump article))
+ (not (funcall gnus-async-prefetch-article-p d)))
+ ;; Not already fetched -- so we add it to the list.
+ (push article gnus-async-fetch-list)))
+ (setq gnus-async-fetch-list
+ (nreverse gnus-async-fetch-list))))
+
+ (when do-fetch
+ (setq article (car gnus-async-fetch-list))))
+
(when (and do-fetch article)
;; We want to fetch some more articles.
(save-excursion
(goto-char (point-max))
(setq mark (point-marker))
(let ((nnheader-callback-function
- (gnus-make-async-article-function
+ (gnus-make-async-article-function
group article mark summary next))
- (nntp-server-buffer (get-buffer
- gnus-async-prefetch-article-buffer)))
- (gnus-message 7 "Prefetching article %d in group %s"
- article group)
+ (nntp-server-buffer
+ (get-buffer gnus-async-prefetch-article-buffer)))
+ (when do-message
+ (gnus-message 7 "Prefetching article %d in group %s"
+ article group))
(gnus-request-article article group))))))))))
(defun gnus-make-async-article-function (group article mark summary next)
"Return a callback function."
`(lambda (arg)
(save-excursion
- (gnus-async-set-buffer)
- (gnus-async-get-semaphore 'gnus-async-article-semaphore)
- (push (list ',(intern (format "%s-%d" group article))
- ,mark (set-marker (make-marker)
- (point-max))
- ,group ,article)
- gnus-async-article-alist)
- (gnus-async-release-semaphore
- 'gnus-async-article-semaphore)
- (when (gnus-buffer-live-p ,summary)
- (gnus-async-prefetch-article
- ,group ,next ,summary t)))))
+ (when arg
+ (gnus-async-set-buffer)
+ (gnus-async-with-semaphore
+ (push (list ',(intern (format "%s-%d" group article))
+ ,mark (set-marker (make-marker) (point-max))
+ ,group ,article)
+ gnus-async-article-alist)))
+ (if (not (gnus-buffer-live-p ,summary))
+ (gnus-async-with-semaphore
+ (setq gnus-async-fetch-list nil))
+ (gnus-async-prefetch-article ,group ,next ,summary t)))))
+
+(defun gnus-async-unread-p (data)
+ "Return non-nil if DATA represents an unread article."
+ (gnus-data-unread-p data))
(defun gnus-async-request-fetched-article (group article buffer)
"See whether we have ARTICLE from GROUP and put it in BUFFER."
(defun gnus-async-delete-prefected-entry (entry)
"Delete ENTRY from buffer and alist."
- (delete-region (cadr entry) (caddr entry))
- (set-marker (cadr entry) nil)
- (set-marker (caddr entry) nil)
- (gnus-async-get-semaphore 'gnus-async-article-semaphore)
- (setq gnus-async-article-alist
- (delq entry gnus-async-article-alist))
- (gnus-async-release-semaphore 'gnus-async-article-semaphore))
+ (ignore-errors
+ (delete-region (cadr entry) (caddr entry))
+ (set-marker (cadr entry) nil)
+ (set-marker (caddr entry) nil))
+ (gnus-async-with-semaphore
+ (setq gnus-async-article-alist
+ (delq entry gnus-async-article-alist))))
(defun gnus-async-prefetch-remove-group (group)
"Remove all articles belonging to GROUP from the prefetch buffer."
(when (equal group (nth 3 (car alist)))
(gnus-async-delete-prefected-entry (car alist)))
(pop alist))))))
-
+
(defun gnus-async-prefetched-article-entry (group article)
"Return the entry for ARTICLE in GROUP iff it has been prefetched."
- (assq (intern (format "%s-%d" group article))
- gnus-async-article-alist))
+ (let ((entry (assq (intern (format "%s-%d" group article))
+ gnus-async-article-alist)))
+ ;; Perhaps something has emptied the buffer?
+ (if (and entry
+ (= (cadr entry) (caddr entry)))
+ (progn
+ (ignore-errors
+ (set-marker (cadr entry) nil)
+ (set-marker (caddr entry) nil))
+ (setq gnus-async-article-alist
+ (delq entry gnus-async-article-alist))
+ nil)
+ entry)))
;;;
;;; Header prefetch
(erase-buffer)
(setq gnus-async-header-prefetched nil)
t)))
-
+
(provide 'gnus-async)
;;; gnus-async.el ends here
projects / gnus / blobdiff