Plumbing for TCP FastOpen for SSL sockets.

net/socket/transport_client_socket_pool.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 "net/socket/transport_client_socket_pool.h"
 
 #include <algorithm>
 
 #include "base/compiler_specific.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/string_util.h"
 #include "base/synchronization/lock.h"
 #include "base/time/time.h"
 #include "base/values.h"
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_log.h"
 #include "net/socket/client_socket_factory.h"
 #include "net/socket/client_socket_handle.h"
 #include "net/socket/client_socket_pool_base.h"
 #include "net/socket/socket_net_log_params.h"
 #include "net/socket/tcp_client_socket.h"
 
 using base::TimeDelta;
+extern bool g_tcp_fastopen_user_enabled;
+extern bool g_tcp_fastopen_supported;

[mmenke, 2014/09/05 19:36:42]

These values don't exist on windows.  Also, think it makes more sense just to
add accessors (And put them in an anonymous namespace in the other file), rather
than using externs.

 
 namespace net {
 
 // TODO(willchan): Base this off RTT instead of statically setting it. Note we
 // choose a timeout that is different from the backup connect job timer so they
 // don't synchronize.
 const int TransportConnectJobHelper::kIPv6FallbackTimerInMs = 300;
 
 namespace {
 
@@ skipping 15 matching lines @@
     g_last_connect_time_lock = LAZY_INSTANCE_INITIALIZER;
 
 // |g_last_connect_time| has the last time a connect() call is made.
 static base::LazyInstance<base::TimeTicks>::Leaky
     g_last_connect_time = LAZY_INSTANCE_INITIALIZER;
 
 TransportSocketParams::TransportSocketParams(
     const HostPortPair& host_port_pair,
     bool disable_resolver_cache,
     bool ignore_limits,
-    const OnHostResolutionCallback& host_resolution_callback)
+    const OnHostResolutionCallback& host_resolution_callback,
+    AutoConnectWithWritePolicy auto_connect_with_write_if_supported)
     : destination_(host_port_pair),
       ignore_limits_(ignore_limits),
-      host_resolution_callback_(host_resolution_callback) {
+      host_resolution_callback_(host_resolution_callback),
+      auto_connect_with_write_(auto_connect_with_write_if_supported) {
   if (disable_resolver_cache)
     destination_.set_allow_cached_response(false);
+  // Auto-connect currently translates to only TCP Fast Open.
+  // Enable TCP FastOpen if user wants it and system supports it.
+  if (!g_tcp_fastopen_supported)
+    auto_connect_with_write_ = AUTO_CONNECT_DISABLED;

[mmenke, 2014/09/05 19:36:42]

This isn't needed - we already have a check that it's supported before enabling
it.

+  else
+    if (g_tcp_fastopen_user_enabled &&
+        auto_connect_with_write_ == AUTO_CONNECT_USE_DEFAULT)
+      auto_connect_with_write_ = AUTO_CONNECT_ENABLED;
 }
 
 TransportSocketParams::~TransportSocketParams() {}
 
 // TransportConnectJobs will time out after this many seconds.  Note this is
 // the total time, including both host resolution and TCP connect() times.
 //
 // TODO(eroman): The use of this constant needs to be re-evaluated. The time
 // needed for TCPClientSocketXXX::Connect() can be arbitrarily long, since
 // the address list may contain many alternatives, and most of those may
@@ skipping 175 matching lines @@
       interval_between_connects_ = CONNECT_INTERVAL_LE_20MS;
     else
       interval_between_connects_ = CONNECT_INTERVAL_GT_20MS;
   }
 
   helper_.set_next_state(
       TransportConnectJobHelper::STATE_TRANSPORT_CONNECT_COMPLETE);
   transport_socket_ =
       helper_.client_socket_factory()->CreateTransportClientSocket(
           helper_.addresses(), net_log().net_log(), net_log().source());
+
+  if (helper_.params()->auto_connect_with_write() == AUTO_CONNECT_ENABLED)
+    transport_socket_->EnableTCPFastOpen();
+
   int rv = transport_socket_->Connect(helper_.on_io_complete());
   if (rv == ERR_IO_PENDING &&
       helper_.addresses().front().GetFamily() == ADDRESS_FAMILY_IPV6 &&
       !AddressListOnlyContainsIPv6(helper_.addresses())) {
     fallback_timer_.Start(
         FROM_HERE,
         base::TimeDelta::FromMilliseconds(
             TransportConnectJobHelper::kIPv6FallbackTimerInMs),
         this,
         &TransportConnectJob::DoIPv6FallbackTransportConnect);
@@ skipping 261 matching lines @@
     HigherLayeredPool* higher_pool) {
   base_.AddHigherLayeredPool(higher_pool);
 }
 
 void TransportClientSocketPool::RemoveHigherLayeredPool(
     HigherLayeredPool* higher_pool) {
   base_.RemoveHigherLayeredPool(higher_pool);
 }
 
 }  // namespace net