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// Copyright (c) 2006-2008 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_BASE_TCP_CLIENT_SOCKET_H_
#define NET_BASE_TCP_CLIENT_SOCKET_H_
#include "build/build_config.h"
#if defined(OS_WIN)
#include <ws2tcpip.h>
#include "base/object_watcher.h"
#elif defined(OS_POSIX)
struct event; // From libevent
#define SOCKET int
#include "base/message_pump_libevent.h"
#endif
#include "base/scoped_ptr.h"
#include "net/base/address_list.h"
#include "net/base/client_socket.h"
#include "net/base/completion_callback.h"
namespace net {
// A client socket that uses TCP as the transport layer.
//
// NOTE: The implementation supports half duplex only. Read and Write calls
// must not be in progress at the same time.
class TCPClientSocket : public ClientSocket,
#if defined(OS_WIN)
public base::ObjectWatcher::Delegate
#elif defined(OS_POSIX)
public base::MessagePumpLibevent::Watcher
#endif
{
public:
// The IP address(es) and port number to connect to. The TCP socket will try
// each IP address in the list until it succeeds in establishing a
// connection.
explicit TCPClientSocket(const AddressList& addresses);
~TCPClientSocket();
// ClientSocket methods:
virtual int Connect(CompletionCallback* callback);
virtual int ReconnectIgnoringLastError(CompletionCallback* callback);
virtual void Disconnect();
virtual bool IsConnected() const;
// Socket methods:
// Try to transfer buf_len bytes to/from socket.
// If a result is available now, return it; else call back later with one.
// Do not call again until a result is returned!
// If any bytes were transferred, the result is the byte count.
// On error, result is a negative error code; see net/base/net_error_list.h
// TODO: what would a zero return value indicate?
// TODO: support multiple outstanding requests?
virtual int Read(char* buf, int buf_len, CompletionCallback* callback);
virtual int Write(const char* buf, int buf_len, CompletionCallback* callback);
private:
SOCKET socket_;
// The list of addresses we should try in order to establish a connection.
AddressList addresses_;
// Where we are in above list, or NULL if all addrinfos have been tried.
const struct addrinfo* current_ai_;
enum WaitState {
NOT_WAITING,
WAITING_CONNECT,
WAITING_READ,
WAITING_WRITE
};
WaitState wait_state_;
#if defined(OS_WIN)
// base::ObjectWatcher::Delegate methods:
virtual void OnObjectSignaled(HANDLE object);
OVERLAPPED overlapped_;
WSABUF buffer_;
base::ObjectWatcher watcher_;
#elif defined(OS_POSIX)
// The socket's libevent wrapper
scoped_ptr<event> event_;
// Called by MessagePumpLibevent when the socket is ready to do I/O
void OnSocketReady(short flags);
// The buffer used by OnSocketReady to retry Read and Write requests
char* buf_;
int buf_len_;
#endif
// External callback; called when read or write is complete.
CompletionCallback* callback_;
int CreateSocket(const struct addrinfo* ai);
void DoCallback(int rv);
void DidCompleteConnect();
void DidCompleteIO();
};
} // namespace net
#endif // NET_BASE_TCP_CLIENT_SOCKET_H_
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