Adds a method to TCPServerSocket to adopt a socket.

net/socket/socket_posix.cc

 // Copyright 2014 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/socket_posix.h"
 
 #include <errno.h>
 #include <netinet/in.h>
 #include <sys/socket.h>
 #include <utility>
@@ skipping 80 matching lines @@
     int rv = MapSystemError(errno);
     Close();
     return rv;
   }
 
   return OK;
 }
 
 int SocketPosix::AdoptConnectedSocket(SocketDescriptor socket,
                                       const SockaddrStorage& address) {
+  int rv = AdoptUnconnectedSocket(socket);
+  if (rv != OK) {
+    return rv;
+  }

[mmenke, 2017/04/21 19:20:38]

nit:  Don't use braces for one line if bodies.

[Raul Vera, 2017/05/01 05:35:25]

Done. But I'd like to point out that the style guide doesn't say anything about
this, so defaults back to the Google style guide, which says you can do it if
you prefer. I consider one-line if bodies without braces to be bugs waiting to
happen when someone adds a line and doesn't notice that the braces aren't there.
Go even eliminated braceless ifs for this reason, IIRC.

[mmenke, 2017/05/01 18:44:19]

Note that you should generally be consistent with code around you.  In this
case, net/ does not use braces in this case (Largely because Chromium style used
to say not to use braces for single line ifs).

+
+  SetPeerAddress(address);
+  return OK;
+}
+
+int SocketPosix::AdoptUnconnectedSocket(SocketDescriptor socket) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK_EQ(kInvalidSocket, socket_fd_);
 
   socket_fd_ = socket;
 
   if (!base::SetNonBlocking(socket_fd_)) {
     int rv = MapSystemError(errno);
     Close();
     return rv;
   }
 
-  SetPeerAddress(address);
   return OK;
 }
 
 SocketDescriptor SocketPosix::ReleaseConnectedSocket() {
   StopWatchingAndCleanUp();
   SocketDescriptor socket_fd = socket_fd_;
   socket_fd_ = kInvalidSocket;
   return socket_fd;
 }
 
@@ skipping 418 matching lines @@
     write_buf_ = NULL;
     write_buf_len_ = 0;
     write_callback_.Reset();
   }
 
   waiting_connect_ = false;
   peer_address_.reset();
 }
 
 }  // namespace net