From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Chong Yidong Newsgroups: gmane.emacs.devel Subject: Re: Avoid a redirect loop in url-http Date: Thu, 12 Apr 2007 00:18:32 -0400 Message-ID: <87tzvmrzs7.fsf@stupidchicken.com> References: <87hcrp0vzp.fsf@x3y2z1.net> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1176351531 12960 80.91.229.12 (12 Apr 2007 04:18:51 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Thu, 12 Apr 2007 04:18:51 +0000 (UTC) Cc: emacs-devel@gnu.org To: Diane Murray Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Thu Apr 12 06:18:49 2007 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1Hbqlj-0005VP-Ja for ged-emacs-devel@m.gmane.org; Thu, 12 Apr 2007 06:18:47 +0200 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Hbqpq-0001do-KR for ged-emacs-devel@m.gmane.org; Thu, 12 Apr 2007 00:23:02 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Hbqpn-0001Xp-B6 for emacs-devel@gnu.org; Thu, 12 Apr 2007 00:22:59 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Hbqpn-0001X8-0h for emacs-devel@gnu.org; Thu, 12 Apr 2007 00:22:59 -0400 Original-Received: from south-station-annex.mit.edu ([18.72.1.2]) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1Hbqlf-0001TL-2M for emacs-devel@gnu.org; Thu, 12 Apr 2007 00:18:43 -0400 Original-Received: from grand-central-station.mit.edu (GRAND-CENTRAL-STATION.MIT.EDU [18.7.21.82]) by south-station-annex.mit.edu (8.13.6/8.9.2) with ESMTP id l3C4Ifm9027223; Thu, 12 Apr 2007 00:18:41 -0400 (EDT) Original-Received: from outgoing-legacy.mit.edu (OUTGOING-LEGACY.MIT.EDU [18.7.22.104]) by grand-central-station.mit.edu (8.13.6/8.9.2) with ESMTP id l3C4Iahw007477; Thu, 12 Apr 2007 00:18:38 -0400 (EDT) Original-Received: from localhost (SYDNEYPACIFIC-FOUR-NINETY-SEVEN.MIT.EDU [18.95.6.242]) ) by outgoing-legacy.mit.edu (8.13.6/8.12.4) with ESMTP id l3C4IXLx014949; Thu, 12 Apr 2007 00:18:33 -0400 (EDT) Original-Received: from cyd by localhost with local (Exim 3.36 #1 (Debian)) id 1HbqlU-0001sh-00; Thu, 12 Apr 2007 00:18:32 -0400 In-Reply-To: <87hcrp0vzp.fsf@x3y2z1.net> (Diane Murray's message of "Tue\, 10 Apr 2007 05\:05\:46 +0200") User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.0.97 (gnu/linux) X-Scanned-By: MIMEDefang 2.42 X-Spam-Score: 0.001 X-detected-kernel: Solaris 9.1 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:69326 Archived-At: Diane Murray writes: > On occasion url-http gets stuck in an endless redirect loop. This can > be fixed by simply checking if the number of redirected URLs in > `url-callback-arguments' hasn't gone over a certain number (which > could be a customizable variable). If it has been redirected too many > times, rather than call `url-retrieve-internal' again, > `url-http-parse-headers' should just let the callback function get > activated - after adding a redirect error to `url-callback-arguments', > so that the callback knows that the maximum number of redirects was > reached. Thanks. How about this patch? It doesn't implement a defcustom as you suggested; it simply searches for a redirect loop. It also simply signals an error if a loop is found. (The indentation of existing code is left unchanged to make the patch easier to read.) *** emacs/lisp/url/url-http.el.~1.52.~ 2007-04-01 11:32:35.000000000 -0400 --- emacs/lisp/url/url-http.el 2007-04-12 00:17:40.000000000 -0400 *************** *** 555,561 **** (url-expand-file-name redirect-uri url-http-target-url))) (let ((url-request-method url-http-method) (url-request-data url-http-data) ! (url-request-extra-headers url-http-extra-headers)) ;; Remember that the request was redirected. (setf (car url-callback-arguments) (nconc (list :redirect redirect-uri) --- 555,571 ---- (url-expand-file-name redirect-uri url-http-target-url))) (let ((url-request-method url-http-method) (url-request-data url-http-data) ! (url-request-extra-headers url-http-extra-headers) ! (events (car url-callback-arguments))) ! ;; Check for redirect loops ! (while events ! (if (eq (car events) :redirect) ! (and (setq events (cdr events)) ! (if (eq (car events) redirect-uri) ! (error "HTTP redirect loop detected") ! (setq events (cdr events)))) ! (and (setq events (cdr events)) ! (setq events (cdr events))))) ;; Remember that the request was redirected. (setf (car url-callback-arguments) (nconc (list :redirect redirect-uri) *************** *** 570,576 **** (url-retrieve-internal redirect-uri url-callback-function url-callback-arguments)) ! (url-mark-buffer-as-dead (current-buffer)))))) (4 ; Client error ;; 400 Bad Request ;; 401 Unauthorized --- 580,586 ---- (url-retrieve-internal redirect-uri url-callback-function url-callback-arguments)) ! (url-mark-buffer-as-dead (current-buffer))))))) (4 ; Client error ;; 400 Bad Request ;; 401 Unauthorized