Add basic TCP socket mojo implementation

mojo/services/network/tcp_bound_socket_impl.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 "mojo/services/network/tcp_bound_socket_impl.h"
 
 #include "mojo/services/network/net_adapters.h"
 #include "mojo/services/network/net_address_type_converters.h"
 #include "mojo/services/network/tcp_connected_socket_impl.h"
 #include "mojo/services/network/tcp_server_socket_impl.h"
 #include "net/base/net_errors.h"
 
 namespace mojo {
 
 TCPBoundSocketImpl::TCPBoundSocketImpl() {
 }
 
 TCPBoundSocketImpl::~TCPBoundSocketImpl() {
 }
 
 int TCPBoundSocketImpl::Bind(NetAddressPtr local_address) {
-  // The local address might be null to match any port.
-  net::IPEndPoint end_point;
-  if (!local_address.is_null())
-    end_point = local_address.To<net::IPEndPoint>();
+  net::IPEndPoint end_point = local_address.To<net::IPEndPoint>();
 
   socket_.reset(new net::TCPSocket(NULL, net::NetLog::Source()));
   int result = socket_->Open(end_point.GetFamily());
   if (result != net::OK)
     return result;
 
   result = socket_->SetDefaultOptionsForServer();
   if (result != net::OK)
     return result;
 
   result = socket_->Bind(end_point);
   if (result != net::OK)
     return result;
 
   return net::OK;
 }
 
 NetAddressPtr TCPBoundSocketImpl::GetLocalAddress() const {
   net::IPEndPoint resolved_local_address;
   if (socket_->GetLocalAddress(&resolved_local_address) != net::OK)
     return NetAddressPtr();
   return NetAddress::From(resolved_local_address);
 }
 
 void TCPBoundSocketImpl::StartListening(
     InterfaceRequest<TCPServerSocket> server,
     const Callback<void(NetworkErrorPtr)>& callback) {
-  if (!socket_) {
+  if (!socket_ || pending_connect_socket_.is_pending()) {
     // A bound socket will only be returned to the caller after binding
     // succeeds, so if the socket doesn't exist, that means ownership was
     // already passed to a server socket or client socket.
     callback.Run(MakeNetworkError(net::ERR_FAILED));
     return;
   }
 
   // TODO(brettw) set the backlog properly.
   int result = socket_->Listen(4);
   if (result != net::OK) {
     callback.Run(MakeNetworkError(result));
     return;
   }
 
   // The server socket object takes ownership of the socket.
   BindToRequest(new TCPServerSocketImpl(socket_.Pass()), &server);
   callback.Run(MakeNetworkError(net::OK));
 }
 
 void TCPBoundSocketImpl::Connect(
     NetAddressPtr remote_address,
     ScopedDataPipeConsumerHandle send_stream,
     ScopedDataPipeProducerHandle receive_stream,
     InterfaceRequest<TCPConnectedSocket> client_socket,
     const Callback<void(NetworkErrorPtr)>& callback) {
-  // TODO(brettw) write this.
+  if (!socket_ || pending_connect_socket_.is_pending()) {
+    // A bound socket will only be returned to the caller after binding
+    // succeeds, so if the socket doesn't exist, that means ownership was
+    // already passed to a server socket or client socket.
+    callback.Run(MakeNetworkError(net::ERR_FAILED));

[willchan no longer on Chromium, 2014/10/17 00:41:00]

We use ERR_UNEXPECTED for places where we believe the caller is fault.

+    return;
+  }
+
+  net::IPEndPoint end_point = remote_address.To<net::IPEndPoint>();
+
+  pending_connect_send_stream_ = send_stream.Pass();
+  pending_connect_receive_stream_ = receive_stream.Pass();
+  pending_connect_socket_ = client_socket.Pass();
+  pending_connect_callback_ = callback;
+  int result = socket_->Connect(
+      end_point,
+      base::Bind(&TCPBoundSocketImpl::OnConnected, base::Unretained(this)));
+  if (result == net::OK) {
+    OnConnected(result);
+  } else if (result != net::ERR_IO_PENDING) {
+    // Error occurred.
+    pending_connect_send_stream_.reset();
+    pending_connect_receive_stream_.reset();
+    pending_connect_socket_ = InterfaceRequest<TCPConnectedSocket>();
+    pending_connect_callback_ = Callback<void(NetworkErrorPtr)>();
+    callback.Run(MakeNetworkError(result));
+  }
+}
+
+void TCPBoundSocketImpl::OnConnected(int result) {
+  if (result == net::OK) {
+    BindToRequest(new TCPConnectedSocketImpl(
+                      socket_.Pass(),
+                      pending_connect_send_stream_.Pass(),
+                      pending_connect_receive_stream_.Pass()),
+                  &pending_connect_socket_);
+  } else {
+    pending_connect_send_stream_.reset();
+    pending_connect_receive_stream_.reset();
+    pending_connect_socket_ = InterfaceRequest<TCPConnectedSocket>();
+  }
+  pending_connect_callback_.Run(MakeNetworkError(result));

[willchan no longer on Chromium, 2014/10/17 00:41:00]

This works fine here, but in general, for net/ programming, we prefer to store
the async callback in a temporary and NULL out the member variable for the
callback, prior to invoking the callback, in order to handle re-entrancy. This
is just a convention and doesn't matter in this particular case, but I'd
encourage doing it anyway, so people copy/paste a good pattern.

+  pending_connect_callback_ = Callback<void(NetworkErrorPtr)>();
 }
 
 }  // namespace mojo