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 11 namespace chrome_browser_net { 12 ConfigureAsyncDnsFieldTrial()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