From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Kenichi Handa Newsgroups: gmane.emacs.devel Subject: Re: Use of memcmp in font.c Date: Wed, 11 Jun 2008 10:07:38 +0900 Message-ID: References: <87ve0iqnnq.fsf@stupidchicken.com> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 (generated by SEMI 1.14.3 - "Ushinoya") Content-Type: text/plain; charset=US-ASCII X-Trace: ger.gmane.org 1213146484 6230 80.91.229.12 (11 Jun 2008 01:08:04 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 11 Jun 2008 01:08:04 +0000 (UTC) Cc: emacs-devel@gnu.org To: Chong Yidong Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Jun 11 03:08:46 2008 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 1K6EpP-0000Ov-Jk for ged-emacs-devel@m.gmane.org; Wed, 11 Jun 2008 03:08:43 +0200 Original-Received: from localhost ([127.0.0.1]:51970 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1K6Eoc-00078y-6Z for ged-emacs-devel@m.gmane.org; Tue, 10 Jun 2008 21:07:54 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1K6EoX-00077n-MV for emacs-devel@gnu.org; Tue, 10 Jun 2008 21:07:49 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1K6EoV-00075t-7m for emacs-devel@gnu.org; Tue, 10 Jun 2008 21:07:48 -0400 Original-Received: from [199.232.76.173] (port=59555 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1K6EoV-00075l-3Z for emacs-devel@gnu.org; Tue, 10 Jun 2008 21:07:47 -0400 Original-Received: from mx1.aist.go.jp ([150.29.246.133]:57182) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1K6EoU-0005Yr-IK for emacs-devel@gnu.org; Tue, 10 Jun 2008 21:07:47 -0400 Original-Received: from rqsmtp1.aist.go.jp (rqsmtp1.aist.go.jp [150.29.254.115]) by mx1.aist.go.jp with ESMTP id m5B18GXC028205; Wed, 11 Jun 2008 10:08:16 +0900 (JST) env-from (handa@m17n.org) Original-Received: from smtp1.aist.go.jp by rqsmtp1.aist.go.jp with ESMTP id m5B17f04022894; Wed, 11 Jun 2008 10:07:41 +0900 (JST) env-from (handa@m17n.org) Original-Received: by smtp1.aist.go.jp with ESMTP id m5B17cEl001957; Wed, 11 Jun 2008 10:07:38 +0900 (JST) env-from (handa@m17n.org) Original-Received: from handa by etlken.m17n.org with local (Exim 4.69) (envelope-from ) id 1K6EoM-0002o3-L1; Wed, 11 Jun 2008 10:07:38 +0900 In-reply-to: <87ve0iqnnq.fsf@stupidchicken.com> (message from Chong Yidong on Mon, 09 Jun 2008 17:55:05 -0400) User-Agent: SEMI/1.14.3 (Ushinoya) FLIM/1.14.2 (Yagi-Nishiguchi) APEL/10.2 Emacs/23.0.60 (i686-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) X-detected-kernel: by monty-python.gnu.org: Solaris 9 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:98908 Archived-At: In article <87ve0iqnnq.fsf@stupidchicken.com>, Chong Yidong writes: > Is the use of memcmp in font.c:1384 safe? It seems to me that if the > string being parsed ends early, we'll get a segmentation fault. > /* Now parse ":KEY=VAL" patterns. Store known keys and values in > extra, copy unknown ones to COPY. It is stored in extra slot by > the key QCfc_unknown_spec. */ > while (*p0) > { > Lisp_Object key, val; > int prop; > for (p1 = p0 + 1; *p1 && *p1 != '=' && *p1 != ':'; p1++); > if (*p1 != '=') > { > /* Must be an enumerated value. */ > val = font_intern_prop (p0 + 1, p1 - p0 - 1); > if (memcmp (p0 + 1, "light", 5) == 0 > || memcmp (p0 + 1, "medium", 6) == 0 > ..... I've thought that memcmp doesn't check bytes after the first non-matching byte and thus the above are safe because p0 is null-terminated. --- Kenichi Handa handa@ni.aist.go.jp