Add a mechanism to disable IPv6....

chrome/browser/net/dns_global.cc

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/net/dns_global.h"
 
 #include <map>
 #include <string>
 
 #include "base/singleton.h"
 #include "base/stats_counters.h"
 #include "base/string_util.h"
 #include "base/thread.h"
 #include "base/values.h"
 #include "chrome/browser/browser.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/net/dns_host_info.h"
 #include "chrome/browser/net/referrer.h"
 #include "chrome/browser/profile.h"
 #include "chrome/browser/session_startup_pref.h"
 #include "chrome/common/notification_registrar.h"
 #include "chrome/common/notification_service.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/pref_service.h"
+#include "chrome/common/chrome_switches.h"
 #include "net/base/host_resolver.h"
+#include "net/base/host_resolver_impl.h"
 
 using base::Time;
 using base::TimeDelta;
 
 namespace chrome_browser_net {
 
 static void DiscardAllPrefetchState();
 static void DnsMotivatedPrefetch(const std::string& hostname,
                                  DnsHostInfo::ResolutionMotivation motivation);
 static void DnsPrefetchMotivatedList(
@@ skipping 434 matching lines @@
     return;
   dns_master->DiscardAllResults();
 }
 
 //------------------------------------------------------------------------------
 
 net::HostResolver* GetGlobalHostResolver() {
   // Called from UI thread.
   if (!global_host_resolver) {
     global_host_resolver = net::CreateSystemHostResolver();
+
+    if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kDisableIPv6))
+      global_host_resolver->DisableIPv6(true);
   }
   return global_host_resolver;
 }
 
 //------------------------------------------------------------------------------
 // Functions to handle saving of hostnames from one session to the next, to
 // expedite startup times.
 
 void SaveHostNamesForNextStartup(PrefService* local_state) {
   if (!dns_prefetch_enabled)
@@ skipping 125 matching lines @@
   }
 }
 
 DnsPrefetcherInit::~DnsPrefetcherInit() {
     if (dns_master)
       FreeDnsPrefetchResources();
   }
 
 }  // namespace chrome_browser_net