From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 15804 invoked by alias); 20 Jul 2011 15:05:09 -0000 Received: (qmail 15783 invoked by uid 22791); 20 Jul 2011 15:05:09 -0000 X-SWARE-Spam-Status: No, hits=-6.9 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD,SPF_HELO_PASS X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 20 Jul 2011 15:04:25 +0000 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p6KF4HeV016328 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 20 Jul 2011 11:04:18 -0400 Received: from localhost.localdomain (ovpn01.gateway.prod.ext.phx2.redhat.com [10.5.9.1]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id p6KF4GMo026547; Wed, 20 Jul 2011 11:04:17 -0400 From: Phil Muldoon To: Pedro Alves Cc: gdb-patches@sourceware.org Subject: Re: [rfc] Prompt memory management/cleanups References: <201107201514.46833.pedro@codesourcery.com> <201107201543.12940.pedro@codesourcery.com> Reply-to: pmuldoon@redhat.com X-URL: http://www.redhat.com Date: Wed, 20 Jul 2011 15:06:00 -0000 In-Reply-To: <201107201543.12940.pedro@codesourcery.com> (Pedro Alves's message of "Wed, 20 Jul 2011 15:43:12 +0100") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-IsSubscribed: yes Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2011-07/txt/msg00532.txt.bz2 Pedro Alves writes: > On Wednesday 20 July 2011 15:30:19, Phil Muldoon wrote: >> s = get_prompt (0) >> set_prompt (s, 0) >> >> Without that check, 'PROMPT (level)' would be freed, but 's' points to >> that. So you set garbage. get_prompt returns a pointer, not a copy. > > I'm probably missing something, but isn't it just > a matter of instead of having: > > + xfree (PROMPT (level)); > + PROMPT (level) = xstrdup (s); > > you have: > > + char *newp = xstrdup (s); > + xfree (PROMPT (level)); > + PROMPT (level) = newp; > > ? Yeah I noted we could do that in my reply. Sure we can do that, I'm not opposed to it. But I am not sure on your objection to the check we make first instead of the xstrdup? If PROMPT (level) == s, then there is no need to copy the contents of s into PROMPT, it is already there? The user is effectively asking for a noop? Cheers, Phil