Plumbing for TCP FastOpen for SSL sockets.

net/socket/tcp_socket.h

 // Copyright 2013 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.
 
 #ifndef NET_SOCKET_TCP_SOCKET_H_
 #define NET_SOCKET_TCP_SOCKET_H_
 
 #include "build/build_config.h"
 #include "net/base/net_export.h"
 
 #if defined(OS_WIN)
 #include "net/socket/tcp_socket_win.h"
 #elif defined(OS_POSIX)
 #include "net/socket/tcp_socket_libevent.h"
 #endif
 
 namespace net {
 
-// Enable/disable experimental TCP FastOpen option.
+// Check if TCP FastOpen option is supported by the OS.
+bool IsTCPFastOpenSupported();
+
+// Check if TCP FastOpen option is enabled.
+bool IsTCPFastOpenEnabled();
+
+// Checks if TCP FastOpen is supported by the kernel. Also enables TFO for all
+// connections if indicated by user.
 // Not thread safe.  Must be called during initialization/startup only.
-NET_EXPORT void SetTCPFastOpenEnabled(bool value);
-
-// Check if the TCP FastOpen option is enabled.
-bool IsTCPFastOpenEnabled();
+NET_EXPORT void CheckSupportAndMaybeEnableTCPFastOpen(bool user_enabled_tfo);

[mmenke, 2014/08/12 15:25:15]

Per earlier comment, "tfo" isn't a standard abbreviation, so should use
something else, either fast_open, or tcp_fast_open... Or just enabled_by_user or
something.

[mmenke, 2014/08/12 15:25:15]

Calling this with false does not indicate to me "Enable this for SSL only if
supported, if passed in false."

[Jana, 2014/08/13 07:33:40]

Changed, PTAL. The initial intent was to indicate "Enable this for all
connections if true is passed in." I hope the new signaling is better ... if
not, please feel free to suggest something better.

[Jana, 2014/08/13 07:33:40]

Done.

 
 // TCPSocket provides a platform-independent interface for TCP sockets.
 //
 // It is recommended to use TCPClientSocket/TCPServerSocket instead of this
 // class, unless a clear separation of client and server socket functionality is
 // not suitable for your use case (e.g., a socket needs to be created and bound
 // before you know whether it is a client or server socket).
 #if defined(OS_WIN)
 typedef TCPSocketWin TCPSocket;
 #elif defined(OS_POSIX)
 typedef TCPSocketLibevent TCPSocket;
 #endif
 
 }  // namespace net
 
 #endif  // NET_SOCKET_TCP_SOCKET_H_