From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Carlos=20Mart=C3=ADn=20Nieto?= Subject: [PATCH] system_path: use a static buffer Date: Thu, 17 Mar 2011 12:01:04 +0100 Message-ID: <1300359664-6230-1-git-send-email-cmn@elego.de> References: <7vipvi7q5g.fsf@alter.siamese.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Junio C Hamano , Erik Faye-Lund To: git@vger.kernel.org X-From: git-owner@vger.kernel.org Thu Mar 17 12:01:16 2011 Return-path: Envelope-to: gcvg-git-2@lo.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Q0Ax8-0007sM-0b for gcvg-git-2@lo.gmane.org; Thu, 17 Mar 2011 12:01:14 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753596Ab1CQLBI convert rfc822-to-quoted-printable (ORCPT ); Thu, 17 Mar 2011 07:01:08 -0400 Received: from kimmy.cmartin.tk ([91.121.65.165]:33552 "EHLO kimmy.cmartin.tk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753257Ab1CQLBH (ORCPT ); Thu, 17 Mar 2011 07:01:07 -0400 Received: from bee.lab.cmartin.tk (i59F7870A.versanet.de [89.247.135.10]) by kimmy.cmartin.tk (Postfix) with ESMTPA id 8BD3F460FD; Thu, 17 Mar 2011 12:00:59 +0100 (CET) Received: (nullmailer pid 6311 invoked by uid 1000); Thu, 17 Mar 2011 11:01:04 -0000 X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <7vipvi7q5g.fsf@alter.siamese.dyndns.org> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Make system_path behave like the other path functions by using a static buffer, fixing a memory leak. Also make sure the prefix pointer is always initialized to either PREFIX or NULL. git_etc_gitattributes and git_etc_gitconfig are the only users who are affected by this change. Make them use a static buffer, which fits their use better as well. Signed-off-by: Carlos Mart=C3=ADn Nieto --- On mi=C3=A9, 2011-03-16 at 13:43 -0700, Junio C Hamano wrote: Carlos Mart=C3=ADn Nieto writes: >=20 > > Make system_path behave like the other path functions by using a > > static buffer, fixing a memory leak. > > > > Also make sure the prefix pointer is always initialized to either > > PREFIX or NULL. > > > > Signed-off-by: Carlos Mart=C3=ADn Nieto > > --- >=20 > Have you made sure all the callers are Ok with this change? >=20 > If somebody called system_path(GIT_EXEC_PATH), saved the result in a > variable without copying, and then called system_path(ETC_GITATTRIBUT= ES), > his variable may now have a value unrelated to GIT_EXEC_PATH, and you > would fix all such callers to save the value away with strdup(). I checked again, and except for the ones changed in this patch, the rest copy it to their own buffer or pass it to puts, setenv or strbuf_addstr. The way these functions are used suggest the caller expects them to deal with their own memory, so that's what I've done. TBH, valgrind only reports a win of ~6-7kB when doing git log on git.git, but it's a step in the right direction (and adds consistency to system_path, which is the main win). attr.c | 6 +++--- config.c | 6 +++--- exec_cmd.c | 11 ++++++----- 3 files changed, 12 insertions(+), 11 deletions(-) diff --git a/attr.c b/attr.c index 6aff695..64d803f 100644 --- a/attr.c +++ b/attr.c @@ -467,9 +467,9 @@ static void drop_attr_stack(void) =20 const char *git_etc_gitattributes(void) { - static const char *system_wide; - if (!system_wide) - system_wide =3D system_path(ETC_GITATTRIBUTES); + static char system_wide[PATH_MAX]; + if (!system_wide[0]) + strlcpy(system_wide, system_path(ETC_GITATTRIBUTES), PATH_MAX); return system_wide; } =20 diff --git a/config.c b/config.c index 822ef83..cd1c295 100644 --- a/config.c +++ b/config.c @@ -808,9 +808,9 @@ int git_config_from_file(config_fn_t fn, const char= *filename, void *data) =20 const char *git_etc_gitconfig(void) { - static const char *system_wide; - if (!system_wide) - system_wide =3D system_path(ETC_GITCONFIG); + static char system_wide[PATH_MAX]; + if (!system_wide[0]) + strlcpy(system_wide, system_path(ETC_GITCONFIG), PATH_MAX); return system_wide; } =20 diff --git a/exec_cmd.c b/exec_cmd.c index 38545e8..5686952 100644 --- a/exec_cmd.c +++ b/exec_cmd.c @@ -9,11 +9,11 @@ static const char *argv0_path; const char *system_path(const char *path) { #ifdef RUNTIME_PREFIX - static const char *prefix; + static const char *prefix =3D NULL; #else static const char *prefix =3D PREFIX; #endif - struct strbuf d =3D STRBUF_INIT; + static char buf[PATH_MAX]; =20 if (is_absolute_path(path)) return path; @@ -33,9 +33,10 @@ const char *system_path(const char *path) } #endif =20 - strbuf_addf(&d, "%s/%s", prefix, path); - path =3D strbuf_detach(&d, NULL); - return path; + if (snprintf(buf, sizeof(buf), "%s/%s", prefix, path) >=3D sizeof(buf= )) + die("system path too long for %s", path); + + return buf; } =20 const char *git_extract_argv0_path(const char *argv0) --=20 1.7.4.1