chrome/browser/net/async_dns_field_trial.cc

   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
  13 bool 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