Plumbing for TCP FastOpen for SSL sockets.

chrome/browser/io_thread.cc

 // Copyright (c) 2012 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/io_thread.h"
 
 #include <vector>
 
 #include "base/base64.h"
 #include "base/bind.h"
@@ skipping 829 matching lines @@
     }
 
     if (command_line.HasSwitch(switches::kEnableWebSocketOverSpdy))
       globals_->enable_websocket_over_spdy.set(true);
   }
 
   // TODO(rch): Make the client socket factory a per-network session
   // instance, constructed from a NetworkSession::Params, to allow us
   // to move this option to IOThread::Globals &
   // HttpNetworkSession::Params.
-  if (command_line.HasSwitch(switches::kEnableTcpFastOpen))
-    net::SetTCPFastOpenEnabled(true);
+
+  bool always_enable_if_supported =
+    command_line.HasSwitch(switches::kEnableTcpFastOpen);
+  // Check for OS support of TCP FastOpen, and turn it on for all connections
+  // if indicated by user.
+  net::CheckSupportAndMaybeEnableTCPFastOpen(always_enable_if_supported);
 }
 
 void IOThread::ConfigureSpdyFromTrial(const std::string& spdy_trial_group,
                                       Globals* globals) {
   if (spdy_trial_group == kSpdyFieldTrialHoldbackGroupName) {
     // TODO(jgraettinger): Use net::NextProtosHttpOnly() instead?
     net::HttpStreamFactory::set_spdy_enabled(false);
   } else if (spdy_trial_group == kSpdyFieldTrialHoldbackControlGroupName) {
     // Use the current SPDY default (SPDY/3.1).
     globals->next_protos = net::NextProtosSpdy31();
@@ skipping 552 matching lines @@
   net::QuicVersionVector supported_versions = net::QuicSupportedVersions();
   for (size_t i = 0; i < supported_versions.size(); ++i) {
     net::QuicVersion version = supported_versions[i];
     if (net::QuicVersionToString(version) == quic_version) {
       return version;
     }
   }
 
   return net::QUIC_VERSION_UNSUPPORTED;
 }