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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
#include <sys/socket.h> // for struct sockaddr
#define SOCKET int
#include "base/message_loop.h"
#endif
#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 windows implementation supports half duplex only.
// Read and Write calls must not be in progress at the same time.
// The libevent implementation supports full duplex because that
// made it slightly easier to implement ssl.
class TCPClientSocket : public ClientSocket,
#if defined(OS_WIN)
public base::ObjectWatcher::Delegate
#elif defined(OS_POSIX)
public MessageLoopForIO::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;
virtual bool IsConnectedAndIdle() const;
// Socket methods:
// Multiple outstanding requests are not supported.
// Full duplex mode (reading and writing at the same time) is not supported
// on Windows (but is supported on Linux and Mac for ease of implementation
// of SSLClientSocket)
virtual int Read(char* buf, int buf_len, CompletionCallback* callback);
virtual int Write(const char* buf, int buf_len, CompletionCallback* callback);
#if defined(OS_POSIX)
// Identical to posix system call of same name
// Needed by ssl_client_socket_nss
virtual int GetPeerName(struct sockaddr *name, socklen_t *namelen);
#endif
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_;
#if defined(OS_WIN)
enum WaitState {
NOT_WAITING,
WAITING_CONNECT,
WAITING_READ,
WAITING_WRITE
};
WaitState wait_state_;
// base::ObjectWatcher::Delegate methods:
virtual void OnObjectSignaled(HANDLE object);
// Waits for the (manual-reset) event object to become signaled and resets
// it. Called after a Winsock function succeeds synchronously
//
// Our testing shows that except in rare cases (when running inside QEMU),
// the event object is already signaled at this point, so we just call this
// method on the IO thread to avoid a context switch.
void WaitForAndResetEvent();
OVERLAPPED overlapped_;
WSABUF buffer_;
base::ObjectWatcher watcher_;
void DidCompleteIO();
#elif defined(OS_POSIX)
// Whether we're currently waiting for connect() to complete
bool waiting_connect_;
// The socket's libevent wrapper
MessageLoopForIO::FileDescriptorWatcher socket_watcher_;
// Called by MessagePumpLibevent when the socket is ready to do I/O
void OnFileCanReadWithoutBlocking(int fd);
void OnFileCanWriteWithoutBlocking(int fd);
// The buffer used by OnSocketReady to retry Read requests
char* buf_;
int buf_len_;
// The buffer used by OnSocketReady to retry Write requests
const char* write_buf_;
int write_buf_len_;
// External callback; called when write is complete.
CompletionCallback* write_callback_;
void DoWriteCallback(int rv);
void DidCompleteRead();
void DidCompleteWrite();
#endif
// External callback; called when read (and on Windows, write) is complete.
CompletionCallback* callback_;
int CreateSocket(const struct addrinfo* ai);
void DoCallback(int rv);
void DidCompleteConnect();
};
} // namespace net
#endif // NET_BASE_TCP_CLIENT_SOCKET_H_
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