1// Copyright (c) 2012 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#include "chrome/browser/net/async_dns_field_trial.h" 6 7#include "base/metrics/field_trial.h" 8#include "base/strings/string_util.h" 9#include "build/build_config.h" 10 11namespace chrome_browser_net { 12 13bool ConfigureAsyncDnsFieldTrial() { 14#if defined(OS_ANDROID) || defined(OS_IOS) 15 // There is no DnsConfigService on those platforms so disable the field trial. 16 return false; 17#endif 18 19#if defined(OS_CHROMEOS) || defined(OS_LINUX) || defined(OS_MACOSX) 20 const bool kDefault = true; 21#else 22 const bool kDefault = false; 23#endif 24 25 // Configure the AsyncDns field trial as follows: 26 // groups AsyncDnsA and AsyncDnsB: return true, 27 // groups SystemDnsA and SystemDnsB: return false, 28 // otherwise (trial absent): return default. 29 std::string group_name = base::FieldTrialList::FindFullName("AsyncDns"); 30 if (!group_name.empty()) 31 return StartsWithASCII(group_name, "AsyncDns", false /* case_sensitive */); 32 return kDefault; 33} 34 35} // namespace chrome_browser_net 36