From mboxrd@z Thu Jan 1 00:00:00 1970 From: Junio C Hamano Subject: Re: [PATCH 2/4] Use strbuf in http code Date: Sun, 09 Dec 2007 10:15:15 -0800 Message-ID: <7vy7c3pwek.fsf@gitster.siamese.dyndns.org> References: <1197219900-19334-1-git-send-email-mh@glandium.org> <1197219900-19334-2-git-send-email-mh@glandium.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: git@vger.kernel.org, Nick Hengeveld To: Mike Hommey X-From: git-owner@vger.kernel.org Sun Dec 09 19:15:55 2007 Return-path: Envelope-to: gcvg-git-2@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1J1Qgw-0001Le-6a for gcvg-git-2@gmane.org; Sun, 09 Dec 2007 19:15:50 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751197AbXLISP3 (ORCPT ); Sun, 9 Dec 2007 13:15:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751192AbXLISP3 (ORCPT ); Sun, 9 Dec 2007 13:15:29 -0500 Received: from a-sasl-quonix.pobox.com ([208.72.237.25]:38104 "EHLO sasl.smtp.pobox.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751170AbXLISP2 (ORCPT ); Sun, 9 Dec 2007 13:15:28 -0500 Received: from a-sasl-quonix (localhost [127.0.0.1]) by a-sasl-quonix.pobox.com (Postfix) with ESMTP id 437535B99; Sun, 9 Dec 2007 13:15:22 -0500 (EST) Received: from pobox.com (ip68-225-240-77.oc.oc.cox.net [68.225.240.77]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by a-sasl-quonix.pobox.com (Postfix) with ESMTP id A408B5B97; Sun, 9 Dec 2007 13:15:17 -0500 (EST) User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Mike Hommey writes: > Also, replace whitespaces with tabs in some places > > Signed-off-by: Mike Hommey > --- > > While testing this, I noticed 3 things: > - CURL_MULTI makes the code very racy > - a lot of the code doesn't do anything useful without CURL_MULTI > - the code is redundant Yeah, there does seem to be a lot of duplicated code that does common setup with slightly different request string. > @@ -1115,16 +1109,11 @@ static char *quote_ref_url(const char *base, const char *ref) > > int fetch_ref(char *ref, unsigned char *sha1) > { > - char *url; > - char hex[42]; > - struct buffer buffer; > + char *url; > + struct strbuf buffer = STRBUF_INIT; > char *base = remote->url; > struct active_request_slot *slot; > struct slot_results results; > - buffer.size = 41; > - buffer.posn = 0; > - buffer.buffer = hex; > - hex[41] = '\0'; > > url = quote_ref_url(base, ref); > slot = get_active_slot(); > @@ -1142,9 +1131,9 @@ int fetch_ref(char *ref, unsigned char *sha1) > return error("Unable to start request"); > } > > - hex[40] = '\0'; > - get_sha1_hex(hex, sha1); > - return 0; > + buffer.buf[40] = '\0'; > + get_sha1_hex(buffer.buf, sha1); > + return 0; > } A conversion like this is worrysome and needs to be rethought I think. At least with the old code, we knew hex[40] was a safe location to make assignment to, even though we did not check if what it contained made sense --- the other end might have had a garbage in that URL (but the caller hopefully would be responsible for noticing that). But with your change, I do not think you have that guarantee. fwrite_buffer() may have extended the buffer using strbuf API, but it may have received less than what you are expecting, in which case you may not have buf[40] touchable for you, no? I at the same time think the original code is buggy. It initializes buffer.buffer to the on-stack storage hex[], but lets fwrite_buffer() to call xrealloc() on it.