33muduo_net库源码分析（九）

1.TcpServer/TcpConnection

（1）Acceptor类的主要功能是socket、bind、listen

（2）一般来说，在上层应用程序中，我们不直接使用Acceptor，而是把它作为TcpServer的成员TcpServer还包含了一个TcpConnection列表

（3）TcpConnection与Acceptor类似，有两个重要的数据成员，Socket与Channel

2.时序图

3.代码

1.TcpConnection.h

// Copyright 2010, Shuo Chen.  All rights reserved.// http://code.google.com/p/muduo///// Use of this source code is governed by a BSD-style license// that can be found in the License file.// Author: Shuo Chen (chenshuo at chenshuo dot com)//// This is a public header file, it must only include public header files.#ifndef MUDUO_NET_TCPCONNECTION_H#define MUDUO_NET_TCPCONNECTION_H#include <muduo/base/Mutex.h>#include <muduo/base/StringPiece.h>#include <muduo/base/Types.h>#include <muduo/net/Callbacks.h>//#include <muduo/net/Buffer.h>#include <muduo/net/InetAddress.h>//#include <boost/any.hpp>#include <boost/enable_shared_from_this.hpp>#include <boost/noncopyable.hpp>#include <boost/scoped_ptr.hpp>#include <boost/shared_ptr.hpp>namespace muduo{namespace net{class Channel;class EventLoop;class Socket;////// TCP connection, for both client and server usage.////// This is an interface class, so don't expose too much details.class TcpConnection : boost::noncopyable,                      public boost::enable_shared_from_this<TcpConnection>{ public:  /// Constructs a TcpConnection with a connected sockfd  ///  /// User should not create this object.  TcpConnection(EventLoop* loop,                const string& name,                int sockfd,                const InetAddress& localAddr,                const InetAddress& peerAddr);  ~TcpConnection();  EventLoop* getLoop() const { return loop_; }  const string& name() const { return name_; }  const InetAddress& localAddress() { return localAddr_; }  const InetAddress& peerAddress() { return peerAddr_; }  bool connected() const { return state_ == kConnected; }  void setConnectionCallback(const ConnectionCallback& cb)  { connectionCallback_ = cb; }  void setMessageCallback(const MessageCallback& cb)  { messageCallback_ = cb; }  // called when TcpServer accepts a new connection  void connectEstablished();   // should be called only once private:  enum StateE { /*kDisconnected, */kConnecting, kConnected/*, kDisconnecting*/ };  void handleRead(Timestamp receiveTime);  void setState(StateE s) { state_ = s; }  EventLoop* loop_;// 所属EventLoop  string name_;// 连接名  StateE state_;  // FIXME: use atomic variable  // we don't expose those classes to client.  boost::scoped_ptr<Socket> socket_;  boost::scoped_ptr<Channel> channel_;  InetAddress localAddr_;  InetAddress peerAddr_;  ConnectionCallback connectionCallback_;  MessageCallback messageCallback_;};typedef boost::shared_ptr<TcpConnection> TcpConnectionPtr;}}#endif  // MUDUO_NET_TCPCONNECTION_H

2.TcpConnection.cc

// Copyright 2010, Shuo Chen.  All rights reserved.// http://code.google.com/p/muduo///// Use of this source code is governed by a BSD-style license// that can be found in the License file.// Author: Shuo Chen (chenshuo at chenshuo dot com)#include <muduo/net/TcpConnection.h>#include <muduo/base/Logging.h>#include <muduo/net/Channel.h>#include <muduo/net/EventLoop.h>#include <muduo/net/Socket.h>#include <muduo/net/SocketsOps.h>#include <boost/bind.hpp>#include <errno.h>#include <stdio.h>using namespace muduo;using namespace muduo::net;/*void muduo::net::defaultConnectionCallback(const TcpConnectionPtr& conn){  LOG_TRACE << conn->localAddress().toIpPort() << " -> "            << conn->peerAddress().toIpPort() << " is "            << (conn->connected() ? "UP" : "DOWN");}void muduo::net::defaultMessageCallback(const TcpConnectionPtr&,                                        Buffer* buf,                                        Timestamp){  buf->retrieveAll();}*/TcpConnection::TcpConnection(EventLoop* loop,                             const string& nameArg,                             int sockfd,                             const InetAddress& localAddr,                             const InetAddress& peerAddr)  : loop_(CHECK_NOTNULL(loop)),    name_(nameArg),    state_(kConnecting),    socket_(new Socket(sockfd)),    channel_(new Channel(loop, sockfd)),    localAddr_(localAddr),    peerAddr_(peerAddr)/*,    highWaterMark_(64*1024*1024)*/{  // 通道可读事件到来的时候，回调TcpConnection::handleRead，_1是事件发生时间  channel_->setReadCallback(      boost::bind(&TcpConnection::handleRead, this, _1));  LOG_DEBUG << "TcpConnection::ctor[" <<  name_ << "] at " << this            << " fd=" << sockfd;  socket_->setKeepAlive(true);}TcpConnection::~TcpConnection(){  LOG_DEBUG << "TcpConnection::dtor[" <<  name_ << "] at " << this            << " fd=" << channel_->fd();}void TcpConnection::connectEstablished(){  loop_->assertInLoopThread();  assert(state_ == kConnecting);  setState(kConnected);  channel_->tie(shared_from_this());  channel_->enableReading();// TcpConnection所对应的通道加入到Poller关注  connectionCallback_(shared_from_this());}void TcpConnection::handleRead(Timestamp receiveTime){  /*  loop_->assertInLoopThread();  int savedErrno = 0;  ssize_t n = inputBuffer_.readFd(channel_->fd(), &savedErrno);  if (n > 0)  {    messageCallback_(shared_from_this(), &inputBuffer_, receiveTime);  }  else if (n == 0)  {    handleClose();  }  else  {    errno = savedErrno;    LOG_SYSERR << "TcpConnection::handleRead";    handleError();  }  */  loop_->assertInLoopThread();  char buf[65536];  ssize_t n = ::read(channel_->fd(), buf, sizeof buf);  messageCallback_(shared_from_this(), buf, n);}

3.TcpServer.h

// Copyright 2010, Shuo Chen.  All rights reserved.// http://code.google.com/p/muduo///// Use of this source code is governed by a BSD-style license// that can be found in the License file.// Author: Shuo Chen (chenshuo at chenshuo dot com)//// This is a public header file, it must only include public header files.#ifndef MUDUO_NET_TCPSERVER_H#define MUDUO_NET_TCPSERVER_H#include <muduo/base/Types.h>#include <muduo/net/TcpConnection.h>#include <map>#include <boost/noncopyable.hpp>#include <boost/scoped_ptr.hpp>namespace muduo{namespace net{class Acceptor;class EventLoop;////// TCP server, supports single-threaded and thread-pool models.////// This is an interface class, so don't expose too much details.class TcpServer : boost::noncopyable{ public:  //typedef boost::function<void(EventLoop*)> ThreadInitCallback;  //TcpServer(EventLoop* loop, const InetAddress& listenAddr);  TcpServer(EventLoop* loop,            const InetAddress& listenAddr,            const string& nameArg);  ~TcpServer();  // force out-line dtor, for scoped_ptr members.  const string& hostport() const { return hostport_; }  const string& name() const { return name_; }  /// Starts the server if it's not listenning.  ///  /// It's harmless to call it multiple times.  /// Thread safe.  void start();  /// Set connection callback.  /// Not thread safe.  // 设置连接到来或者连接关闭回调函数  void setConnectionCallback(const ConnectionCallback& cb)  { connectionCallback_ = cb; }  /// Set message callback.  /// Not thread safe.  // 设置消息到来回调函数  void setMessageCallback(const MessageCallback& cb)  { messageCallback_ = cb; } private:  /// Not thread safe, but in loop  void newConnection(int sockfd, const InetAddress& peerAddr);  typedef std::map<string, TcpConnectionPtr> ConnectionMap;  EventLoop* loop_;  // the acceptor loop  const string hostport_;// 服务端口  const string name_;// 服务名  boost::scoped_ptr<Acceptor> acceptor_; // avoid revealing Acceptor  ConnectionCallback connectionCallback_;  MessageCallback messageCallback_;  bool started_;  // always in loop thread  int nextConnId_;// 下一个连接ID  ConnectionMap connections_;// 连接列表};}}#endif  // MUDUO_NET_TCPSERVER_H

4.TcpServer.cc

// Copyright 2010, Shuo Chen.  All rights reserved.// http://code.google.com/p/muduo///// Use of this source code is governed by a BSD-style license// that can be found in the License file.// Author: Shuo Chen (chenshuo at chenshuo dot com)#include <muduo/net/TcpServer.h>#include <muduo/base/Logging.h>#include <muduo/net/Acceptor.h>#include <muduo/net/EventLoop.h>//#include <muduo/net/EventLoopThreadPool.h>#include <muduo/net/SocketsOps.h>#include <boost/bind.hpp>#include <stdio.h>  // snprintfusing namespace muduo;using namespace muduo::net;TcpServer::TcpServer(EventLoop* loop,                     const InetAddress& listenAddr,                     const string& nameArg)  : loop_(CHECK_NOTNULL(loop)),    hostport_(listenAddr.toIpPort()),    name_(nameArg),    acceptor_(new Acceptor(loop, listenAddr)),    /*threadPool_(new EventLoopThreadPool(loop)),    connectionCallback_(defaultConnectionCallback),    messageCallback_(defaultMessageCallback),*/    started_(false),    nextConnId_(1){  // Acceptor::handleRead函数中会回调用TcpServer::newConnection  // _1对应的是socket文件描述符，_2对应的是对等方的地址(InetAddress)  acceptor_->setNewConnectionCallback(      boost::bind(&TcpServer::newConnection, this, _1, _2));}TcpServer::~TcpServer(){  loop_->assertInLoopThread();  LOG_TRACE << "TcpServer::~TcpServer [" << name_ << "] destructing";}// 该函数多次调用是无害的// 该函数可以跨线程调用void TcpServer::start(){  if (!started_)  {    started_ = true;  }  if (!acceptor_->listenning())  {// get_pointer返回原生指针    loop_->runInLoop(        boost::bind(&Acceptor::listen, get_pointer(acceptor_)));  }}void TcpServer::newConnection(int sockfd, const InetAddress& peerAddr){  loop_->assertInLoopThread();  char buf[32];  snprintf(buf, sizeof buf, ":%s#%d", hostport_.c_str(), nextConnId_);  ++nextConnId_;  string connName = name_ + buf;  LOG_INFO << "TcpServer::newConnection [" << name_           << "] - new connection [" << connName           << "] from " << peerAddr.toIpPort();  InetAddress localAddr(sockets::getLocalAddr(sockfd));  // FIXME poll with zero timeout to double confirm the new connection  // FIXME use make_shared if necessary  TcpConnectionPtr conn(new TcpConnection(loop_,                                          connName,                                          sockfd,                                          localAddr,                                          peerAddr));  connections_[connName] = conn;  conn->setConnectionCallback(connectionCallback_);  conn->setMessageCallback(messageCallback_);  conn->connectEstablished();}

5.Reactor_test.08.cc

#include <muduo/net/TcpServer.h>#include <muduo/net/EventLoop.h>#include <muduo/net/InetAddress.h>#include <stdio.h>using namespace muduo;using namespace muduo::net;void onConnection(const TcpConnectionPtr& conn){  if (conn->connected())  {    printf("onConnection(): new connection [%s] from %s\n",           conn->name().c_str(),           conn->peerAddress().toIpPort().c_str());  }  else  {    printf("onConnection(): connection [%s] is down\n",           conn->name().c_str());  }}void onMessage(const TcpConnectionPtr& conn,               const char* data,               ssize_t len){  printf("onMessage(): received %zd bytes from connection [%s]\n",         len, conn->name().c_str());}int main(){  printf("main(): pid = %d\n", getpid());  InetAddress listenAddr(8888);  EventLoop loop;  TcpServer server(&loop, listenAddr, "TestServer");  server.setConnectionCallback(onConnection);  server.setMessageCallback(onMessage);  server.start();  loop.loop();}