forked from pool/glibc
125 lines
4.5 KiB
Diff
125 lines
4.5 KiB
Diff
|
From libc-alpha-return-22754-pasky=ucw.cz@sourceware.org Tue Mar 16 00:47:00 2010
|
||
|
|
Return-Path: <libc-alpha-return-22754-pasky=ucw.cz@sourceware.org>
|
||
|
|
X-Original-To: pasky@pasky.or.cz
|
||
|
|
Delivered-To: pasky@pasky.or.cz
|
||
|
|
Received: from nikam.ms.mff.cuni.cz (nikam-dmz.ms.mff.cuni.cz [195.113.20.16])
|
||
|
|
by machine.or.cz (Postfix) with ESMTPS id C1B8586202A
|
||
|
|
for <pasky@pasky.or.cz>; Tue, 16 Mar 2010 00:47:00 +0100 (CET)
|
||
|
|
Received: by nikam.ms.mff.cuni.cz (Postfix)
|
||
|
|
id 9CDEC9AC7A4; Tue, 16 Mar 2010 00:47:00 +0100 (CET)
|
||
|
|
Delivered-To: pasky@kam.mff.cuni.cz
|
||
|
|
Received: from jabberwock.ucw.cz (jabberwock.ucw.cz [89.250.246.4])
|
||
|
|
by nikam.ms.mff.cuni.cz (Postfix) with ESMTP id 99F0E9AC77B
|
||
|
|
for <pasky@kam.mff.cuni.cz>; Tue, 16 Mar 2010 00:47:00 +0100 (CET)
|
||
|
|
Received: from sourceware.org (server1.sourceware.org [209.132.180.131])
|
||
|
|
by jabberwock.ucw.cz (Postfix) with SMTP id 14E1ACF040
|
||
|
|
for <pasky@ucw.cz>; Tue, 16 Mar 2010 00:46:59 +0100 (CET)
|
||
|
|
Received: (qmail 18956 invoked by alias); 15 Mar 2010 23:46:58 -0000
|
||
|
|
Delivered-To: moderator for libc-alpha@sourceware.org
|
||
|
|
Received: (qmail 15843 invoked by uid 22791); 15 Mar 2010 17:23:15 -0000
|
||
|
|
X-SWARE-Spam-Status: No, hits=-2.6 required=5.0
|
||
|
|
tests=BAYES_00
|
||
|
|
X-Spam-Check-By: sourceware.org
|
||
|
|
Message-ID: <4B9E6CFA.7020002@riot.org>
|
||
|
|
Date: Mon, 15 Mar 2010 18:23:06 +0100
|
||
|
|
From: Sebastian Kienzl <seb@riot.org>
|
||
|
|
User-Agent: Thunderbird 2.0.0.23 (Windows/20090812)
|
||
|
|
MIME-Version: 1.0
|
||
|
|
To: libc-alpha@sourceware.org
|
||
|
|
Subject: Reloading of /etc/resolv.conf
|
||
|
|
Content-Type: multipart/mixed;
|
||
|
|
boundary="------------060407080409020101000002"
|
||
|
|
Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm
|
||
|
|
Precedence: bulk
|
||
|
|
List-Id: <libc-alpha.sourceware.org>
|
||
|
|
List-Unsubscribe: <mailto:libc-alpha-unsubscribe-pasky=ucw.cz@sourceware.org>
|
||
|
|
List-Subscribe: <mailto:libc-alpha-subscribe@sourceware.org>
|
||
|
|
List-Archive: <http://sourceware.org/ml/libc-alpha/>
|
||
|
|
List-Post: <mailto:libc-alpha@sourceware.org>
|
||
|
|
List-Help: <mailto:libc-alpha-help@sourceware.org>, <http://sourceware.org/ml/#faqs>
|
||
|
|
Sender: libc-alpha-owner@sourceware.org
|
||
|
|
Delivered-To: mailing list libc-alpha@sourceware.org
|
||
|
|
|
||
|
|
This is a multi-part message in MIME format.
|
||
|
|
--------------060407080409020101000002
|
||
|
|
Content-Type: text/plain; charset=ISO-8859-15; format=flowed
|
||
|
|
Content-Transfer-Encoding: 7bit
|
||
|
|
|
||
|
|
Hello!
|
||
|
|
|
||
|
|
There's a patch in the wild against the resolver which makes it reload
|
||
|
|
/etc/resolv.conf on change, see
|
||
|
|
http://sources.redhat.com/ml/libc-alpha/2004-09/msg00130.html
|
||
|
|
|
||
|
|
However, this patch actually doesn't work properly for multi-threaded
|
||
|
|
programs, as only one thread will notice the change and refresh its
|
||
|
|
resolver state. I've attached a proper patch. It's for 2.5 but it should
|
||
|
|
work with current versions, too.
|
||
|
|
|
||
|
|
Even though the patch may not be interesting for upstream, I decided to
|
||
|
|
let you know about this problem, since the mentioned patch seems to be
|
||
|
|
used by at least Debian and Ubuntu.
|
||
|
|
|
||
|
|
Regards,
|
||
|
|
Seb.
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
--------------060407080409020101000002
|
||
|
|
Content-Type: text/plain;
|
||
|
|
name="glibc-2.5-resolvconf.patch"
|
||
|
|
Content-Transfer-Encoding: 7bit
|
||
|
|
Content-Disposition: inline;
|
||
|
|
filename="glibc-2.5-resolvconf.patch"
|
||
|
|
|
||
|
|
diff -ur resolv.orig/res_libc.c resolv/res_libc.c
|
||
|
|
--- resolv.orig/res_libc.c 2005-11-01 01:06:40.000000000 +0100
|
||
|
|
+++ resolv/res_libc.c 2010-03-15 14:13:18.000000000 +0100
|
||
|
|
@@ -22,7 +22,7 @@
|
||
|
|
#include <arpa/nameser.h>
|
||
|
|
#include <resolv.h>
|
||
|
|
#include <bits/libc-lock.h>
|
||
|
|
-
|
||
|
|
+#include <sys/stat.h>
|
||
|
|
|
||
|
|
/* The following bit is copied from res_data.c (where it is #ifdef'ed
|
||
|
|
out) since res_init() should go into libc.so but the rest of that
|
||
|
|
@@ -89,12 +89,34 @@
|
||
|
|
return (__res_vinit(&_res, 1));
|
||
|
|
}
|
||
|
|
|
||
|
|
+static time_t resconf_mtime;
|
||
|
|
+__libc_lock_define_initialized (static, resconf_mtime_lock);
|
||
|
|
+
|
||
|
|
+/* Check if the modification time of resolv.conf has changed.
|
||
|
|
+ If so, have all threads re-initialize their resolver states */
|
||
|
|
+static void
|
||
|
|
+__res_check_resconf (void)
|
||
|
|
+{
|
||
|
|
+ struct stat statbuf;
|
||
|
|
+ if (stat (_PATH_RESCONF, &statbuf) == 0) {
|
||
|
|
+ __libc_lock_lock (resconf_mtime_lock);
|
||
|
|
+ if (statbuf.st_mtime != resconf_mtime) {
|
||
|
|
+ resconf_mtime = statbuf.st_mtime;
|
||
|
|
+ atomicinclock (lock);
|
||
|
|
+ atomicinc (__res_initstamp);
|
||
|
|
+ atomicincunlock (lock);
|
||
|
|
+ }
|
||
|
|
+ __libc_lock_unlock (resconf_mtime_lock);
|
||
|
|
+ }
|
||
|
|
+}
|
||
|
|
+
|
||
|
|
/* Initialize resp if RES_INIT is not yet set or if res_init in some other
|
||
|
|
thread requested re-initializing. */
|
||
|
|
int
|
||
|
|
__res_maybe_init (res_state resp, int preinit)
|
||
|
|
{
|
||
|
|
if (resp->options & RES_INIT) {
|
||
|
|
+ __res_check_resconf ();
|
||
|
|
if (__res_initstamp != resp->_u._ext.initstamp) {
|
||
|
|
if (resp->nscount > 0) {
|
||
|
|
__res_iclose (resp, true);
|
||
|
|
|
||
|
|
|
||
|
|
--------------060407080409020101000002--
|