目录
1、 TcpConnection.h
2、 TcpConnection.cc
1、 TcpConnection.h
TcpConnection底层绑定(管理)了一个Channel,Channel有事件被Poller通知后,会调用相应的回调,这些回调也是TcpConnection中包含的方法,将这些方法绑定了一下塞给channel作为回调,如果TcpConnection相应的底层对应的channel还在poller上注册着,还会感知到poller通知的事件,并且调用相应的回调,如果此时它对应的TcpConnection对象没有了(被人remove掉)怎么办?
tie使用弱智能指针记录,在处理事件的时候(handleEvent),肯定是被tie过,在这个方法里面将弱智能指针提升一下,如果不做任何的回调调用就说明TcpConnection这个对象已经没有了。
#pragma once
#include "noncopyable.h"
#include "InetAddress.h"
#include "Callbacks.h"
#include "Buffer.h"#include <memory>
#include <string>
#include <atomic>class Channel;
class EventLoop;
class Socket;/*** TcpServer => Acceptor => 有一个新用户连接,通过accept函数拿到connfd* * => TcpConnection 设置回调 =》 Channel => Poller =>Channel的回调操作*
*/
class TcpConnection:noncopyable,public std::enable_shared_from_this<TcpConnection>//获得当前对象的智能指针
{
public:TcpConnection(EventLoop* loop,const std::string& name,int sockfd,const InetAddress& localAddr,const InetAddress& peerAddr);~TcpConnection();EventLoop* getLoop() const {return loop_;}const std::string& name() const{return name_;}const InetAddress& localAddress() const {return localAddr_;}const InetAddress& peerAddress() const {return peerAddr_;}bool connected() const {return state_==kConnected;}//发送数据void send(const std::string& buf);//关闭连接void shutdown();void setConnectionCallback(const ConnectionCallback& cb){connectionCallback_=cb;}void setMessageCallback(const MessageCallback& cb){messageCallback_=cb;}void setWriteCompleteCallback(const WriteCompleteCallback& cb){writeCompleteCallback_=cb;}void setHighWaterMarkCallback(const HighWaterMarkCallback& cb,size_t highWaterMark){highWaterMarkCallback_=cb; highWaterMark_=highWaterMark;}void setCloseCallback(const CloseCallback& cb){closeCallback_=cb;}//连接建立void connectEstablished();//连接销毁void connectDestroyed();
private:enum StateE{kDisconnected,kConnecting,kConnected,kDisconnecting};void setState(StateE state){state_=state;}void handleRead(Timestamp receiveTime);void handleWrite();void handleClose();void handleError();void sendInLoop(const void* message,size_t len);void shutdownInLoop();EventLoop* loop_;//这里绝对不是baseLoop,因为TcpConnection都是在subloop里面管理的const std::string name_;std::atomic_int state_;bool reading_;//这里和Acceptor类似 Acceptor属于mainLoop TcpConnection属于subLoopstd::unique_ptr<Socket> socket_;std::unique_ptr<Channel> channel_;const InetAddress localAddr_;const InetAddress peerAddr_;//回调ConnectionCallback connectionCallback_;//有新连接时的回调MessageCallback messageCallback_;//有读写消息时的回调WriteCompleteCallback writeCompleteCallback_;//消息发送完成以后的回调HighWaterMarkCallback highWaterMarkCallback_;//高水位回调CloseCallback closeCallback_;size_t highWaterMark_;//设置水位线高度//数据的缓冲区Buffer inputBuffer_;//接收数据的缓冲区Buffer outputBuffer_;//发送数据的缓冲区
};
2、 TcpConnection.cc
当在上层调用了某一connection的shutdown()方法,设置当前服务器端的状态是disconnecting,然后执行shutdownInLoop,因为shutdownInLoop关闭了socket的write端,poller就给channel通知了关闭事件,就回调TcpConnection::handclose()方法,handclose()方法相当于将channel所有的事件都去掉。
#include "TcpConnection.h"
#include "Logger.h"
#include "Socket.h"
#include "Channel.h"
#include "EventLoop.h"#include <functional>
#include <errno.h>
#include <memory>
#include <sys/types.h>
#include <sys/socket.h>
#include <strings.h>
#include <netinet/tcp.h>
#include <sys/socket.h>static EventLoop *CheckLoopNotNull(EventLoop *loop)
{if (loop == nullptr){LOG_FATAL("%s:%s:%d TcpConnection Loop is null!\n", __FILE__, __FUNCTION__, __LINE__);}return loop;
}//已建立连接客户端跟服务器之间的联系
TcpConnection::TcpConnection(EventLoop *loop,const std::string &nameArg,int sockfd,const InetAddress &localAddr,const InetAddress &peerAddr): loop_(CheckLoopNotNull(loop)),name_(nameArg),state_(kConnecting),reading_(true),socket_(new Socket(sockfd)),channel_(new Channel(loop,sockfd)),localAddr_(localAddr),peerAddr_(peerAddr),highWaterMark_(64*1024*1024)//64M
{//下面给channel设置相应的回调函数,poller给channel通知感兴趣的事件发生了,channel会回调相应的操作函数channel_->setReadCallback(std::bind(&TcpConnection::handleRead,this,std::placeholders::_1));channel_->setWriteCallback(std::bind(&TcpConnection::handleWrite,this));channel_->setCloseCallback(std::bind(&TcpConnection::handleClose,this));channel_->setErrorCallback(std::bind(&TcpConnection::handleError,this));LOG_INFO("TcpConnection::ctor[%s] at fd=%d\n",name_.c_str(),sockfd);socket_->setKeepAlive(true);//保活机制}TcpConnection::~TcpConnection()
{LOG_INFO("TcpConnection::dtor[%s] at fd=%d state=%d\n",name_.c_str(),channel_->fd(),(int)state_);
}void TcpConnection::send(const std::string& buf)
{if(state_==kConnected){if(loop_->isInLoopThread()){sendInLoop(buf.c_str(),buf.size());}else{loop_->runInLoop(std::bind(&TcpConnection::sendInLoop,this,buf.c_str(),buf.size()));}}
}/*** 发送数据 应用写的快,而内核发送数据慢,需要把待发送数据写入缓冲区,而且设置了水位回调
*/
void TcpConnection::sendInLoop(const void* data,size_t len)
{ssize_t nwrote=0;size_t remaining=len;//没发送完的数据bool faultError=false;//是否发生错误//之前调用过该connection的shutdown,不能再进行发送了if(state_==kDisconnected){LOG_ERROR("disconnected,give up writing!");return;}//表示channel_第一次开始写数据,而且缓冲区没有待发送数据if(!channel_->isWriting()&&outputBuffer_.readableBytes()==0){nwrote=::write(channel_->fd(),data,len);if(nwrote>=0)//发送成功{remaining=len-nwrote;if(remaining==0&&writeCompleteCallback_){//既然在这里数据全部发送完成,就不用再给channel设置epollout事件了loop_->queueInLoop(std::bind(writeCompleteCallback_,shared_from_this()));}}else //nwrote<0{nwrote=0;//errno==EWOULDBLOCK 由于非阻塞,没有数据时正常的返回if(errno!=EWOULDBLOCK)//真正的错误{LOG_ERROR("TcpConnection::sendInLoop");if(errno==EPIPE||errno==ECONNRESET)// SIGPIPE RESET 收到连接重置的请求{faultError=true;}}}}//说明当前这一次write,并没有把数据全部发送出去,剩余的数据需要保存到缓冲区当中,然后给channel//注册epollout事件,poller发现tcp的发送缓冲区有空间,会通知相应的sock-channel,调用writeCallback_回调方法//也就是调用TcpConnection::handleWrite方法,把发送缓冲区中的数据全部发送完成if(!faultError&&remaining>0){//目前发送缓冲区剩余的待发送数据的长度size_t oldLen=outputBuffer_.readableBytes();if(oldLen+remaining>=highWaterMark_&&oldLen<highWaterMark_&&highWaterMarkCallback_){loop_->queueInLoop(std::bind(highWaterMarkCallback_,shared_from_this(),oldLen+remaining));//调用水位线回调}outputBuffer_.append((char*)data+nwrote,remaining);//将待发送数据添加到缓冲区中if(!channel_->isWriting()){channel_->enableWriting();//这里一定要注册channel的写事件,否则poller不会给channel通知epollout}}
}// 关闭连接
void TcpConnection::shutdown()
{if(state_==kConnected){setState(kDisconnecting);loop_->runInLoop(std::bind(&TcpConnection::shutdownInLoop,this));}
}void TcpConnection::shutdownInLoop()
{if(!channel_->isWriting())//说明outputBuffer中的数据已经全部发送完成{socket_->shutdownWrite();//关闭写端}
}// 连接建立
void TcpConnection::connectEstablished()
{setState(kConnected);//设置连接成功状态,初始状态为kConnectingchannel_->tie(shared_from_this());//绑定channel,让这个channel记录一下TcpConnection对象存活的状态channel_->enableReading();//同poller注册channel的epollin事件//新连接建立,执行回调connectionCallback_(shared_from_this());
}// 连接销毁
void TcpConnection::connectDestroyed()
{if(state_==kConnected){setState(kDisconnected);channel_->disableAll();//把channel的所有感兴趣的事件,从poller中del掉 相当于epoll_ctlconnectionCallback_(shared_from_this());//断开连接}channel_->remove();//把channel从poller中删除掉
}void TcpConnection::handleRead(Timestamp receiveTime)
{int savedErrno=0;ssize_t n=inputBuffer_.readFd(channel_->fd(),&savedErrno);if(n>0){//已建立连接的用户,有可读事件发生了,调用用户传入的回调操作omMessagemessageCallback_(shared_from_this(),&inputBuffer_,receiveTime);}else if(n==0){handleClose();}else{errno=savedErrno;LOG_ERROR("TcpConnection::handleRead");handleError();}
}
void TcpConnection::handleWrite()
{if(channel_->isWriting()){int savedErrno=0;ssize_t n=outputBuffer_.writeFd(channel_->fd(),&savedErrno);if(n>0){outputBuffer_.retrieve(n);if(outputBuffer_.readableBytes()==0)//发送完成{channel_->disableWriting();//由可写变为不可写if(writeCompleteCallback_){//唤醒loop_对应的thread线程,执行回调loop_->queueInLoop(//loop一定在TcpConnection所对应的线程中std::bind(writeCompleteCallback_,shared_from_this()));}if(state_==kDisconnecting){shutdownInLoop();}}}else{LOG_ERROR("TcpConnection::handleWrite");}}else//执行handlewrite,但channel并不是可写事件{LOG_ERROR("TcpConnection fd=%d is down,no more writing\n",channel_->fd());}
}//poller=>channel::closeCallback=>TcpConnection::handleClose 回调
void TcpConnection::handleClose()
{LOG_INFO("TcpConnection::handleClose fd=%d state=%d \n",channel_->fd(),(int)state_);setState(kDisconnected);channel_->disableAll();//将channel感兴趣的事件从poller上全部删除TcpConnectionPtr connPtr(shared_from_this());connectionCallback_(connPtr);//执行连接关闭的回调closeCallback_(connPtr);//关闭连接的回调 执行的是TcpServer::removeConnection回调方法
}
void TcpConnection::handleError()
{int optval;socklen_t optlen=sizeof optval;int err=0;if(::getsockopt(channel_->fd(),SOL_SOCKET,SO_ERROR,&optval,&optlen)<0){err = errno;}else{err=optval;}LOG_ERROR("TcpConnection::handleError name:%s-SO_ERROR:%d \n",name_.c_str(),err);
}