TCP网络模型的封装

最近学习了TCP网络模型的封装，其中运用的封装技术个人感觉有点绕

在反复读代码、做思维导图下初步理解了这套封装模型，不禁感叹原来代码还能这样写？神奇！

为此将源码分享出来并将流程图画出，方便理解和复习

PS：下列思维导图仅代表个人理解，如有误恳请指出纠正

模型继承关系图

要理解该模型，我认为首先要画图理解类的继承关系，下面是我画的一个简单关系图

模型流程图

下面是我画的该模型的大致流程图，仅供参考，有误恳请指出

具体代码实现

EventLoop.hpp

#ifndef _EVENTLOOP_H_
#define _EVENTLOOP_H_#include <list>
#include <WinSock2.h>enum class E_Event_Type
{Recv,Send,
};class IEventCallback
{
public:virtual void OnNetEvent(E_Event_Type e) = 0;virtual void OnClose() = 0;
};struct sSelectEvent
{SOCKET sock;IEventCallback* event;
};class EventLoop
{
private:std::list<sSelectEvent*> _events;std::list<sSelectEvent*> _delEventCaches;public:void LoopOnce();void AddEvent(sSelectEvent* e){_events.push_back(e);}void DelEvent(sSelectEvent* e);
};
#endif

EventLoop.cpp

#include "EventLoop.hpp"void EventLoop::LoopOnce()
{fd_set reads;FD_ZERO(&reads);do{auto begin = _events.begin();auto end = _events.end();for (; begin != end; ++begin)FD_SET((*begin)->sock, &reads);//(*begin)->event->NeedWrite()} while (false);int nSeclect = select(0, &reads, nullptr, nullptr, nullptr);if (0 == nSeclect)return;if (nSeclect < 0)return;do{auto begin = _events.begin();auto end = _events.end();for (; begin != end; ++begin){if (FD_ISSET((*begin)->sock, &reads)){(*begin)->event->OnNetEvent(E_Event_Type::Recv);}}} while (false);do{auto begin = _delEventCaches.begin();auto end = _delEventCaches.end();for (; begin != end; ++begin){sSelectEvent* p = *begin;_events.remove_if([p](sSelectEvent* a){return a == p;});p->event->OnClose();}_delEventCaches.clear();} while (false);}void EventLoop::DelEvent(sSelectEvent* e)
{_delEventCaches.push_back(e);
}

TcpListen.hpp

#ifndef _TCPLISTEN_H_
#define _TCPLISTEN_H_
#define _WINSOCK_DEPRECATED_NO_WARNINGS #include "EventLoop.hpp"
#include <WinSock2.h>
#include <iostream>
#include <functional>
class TcpSocket;
class TcpListen :public IEventCallback
{
protected:SOCKET _sock;sSelectEvent _event;EventLoop* _loop;std::function<TcpSocket* ()> _sockCB;
public:TcpListen();void Init(EventLoop* loop, std::function<TcpSocket* ()> sockCB){_loop = loop; _sockCB = sockCB;}bool Listen(unsigned short port, const char* const ip = "0.0.0.0");// 通过 IEventCallback 继承virtual void OnNetEvent(E_Event_Type e) override;virtual void OnClose() override;
public:virtual void OnAccpet(TcpSocket* sock) = 0;};
#endif

TcpListen.cpp

#include "TcpListen.h"
#include "TcpSocket.h"
TcpListen::TcpListen()
{_event.event = this;_sock = _event.sock = INVALID_SOCKET;_loop = nullptr;
}bool TcpListen::Listen(unsigned short port, const char* const ip)
{_sock = socket(AF_INET, SOCK_STREAM, 0);if (INVALID_SOCKET == _sock){std::cout << "create SOCKET fail!\n" << std::endl;return false;}std::cout << "1.create SOCKET OK!\n" << std::endl;// 2.绑定IP和端口
//  bind(SOCKET,绑定的IP端口结构体,结构体大小)SOCKADDR_IN serverAddr;serverAddr.sin_family = AF_INET;//SOCKADDR_IN6*serverAddr.sin_port = htons(port);// 127.0.0.1 本机回环地址// 0.0.0.0  绑定所有IPserverAddr.sin_addr.s_addr = inet_addr(ip);//SOCKADDR_IN6 serverAddr6;if (SOCKET_ERROR== bind(_sock, (SOCKADDR*)&serverAddr, sizeof(serverAddr))){std::cout << "bind SOCKET fail!\n" << std::endl;return false;}std::cout << "2.bind SOCKET OK!\n" << std::endl;listen(_sock, 5);std::cout << "3.listen SOCKET OK!\n" << std::endl;_event.sock = _sock;_loop->AddEvent(&_event);return true;
}void TcpListen::OnNetEvent(E_Event_Type e)
{SOCKADDR_IN clientAddr;int addrlen = sizeof(SOCKADDR_IN);SOCKET clientSock = accept(_sock, (SOCKADDR*)&clientAddr, &addrlen);if (INVALID_SOCKET == clientSock){std::cout << "4.ACCEPT ERROR!!\n" << std::endl;return;}std::cout << "4.ACCEPT ip:" << inet_ntoa(clientAddr.sin_addr)<< "  Port:" << ntohs(clientAddr.sin_port) << "   " << clientSock<< std::endl;TcpSocket* sock = _sockCB();sock->OnAccept(clientSock, &clientAddr);OnAccpet(sock);}void TcpListen::OnClose()
{
}

TcpSocket.hpp

#ifndef _TCPSOCKET_H_
#define _TCPSOCKET_H_
#define _WINSOCK_DEPRECATED_NO_WARNINGS #include "EventLoop.hpp"const unsigned int RECV_MAX_BUF = 4096 * 2;class TcpSocket :public IEventCallback
{
private:SOCKET _sock;SOCKADDR_IN _addr;sSelectEvent _event;EventLoop* _loop;char _recvBuff[RECV_MAX_BUF];int _recvLen;bool _bClose;
public:TcpSocket();virtual ~TcpSocket();void Init(EventLoop* loop);void OnAccept(SOCKET sock, SOCKADDR_IN* addr);void Close();public:// 通过 IEventCallback 继承virtual void OnNetEvent(E_Event_Type e) override;virtual void OnClose() override;public:virtual int OnNetMsg(const char* const msg, int msgLen) = 0;void Send(const char* msg, int msgLen);};#endif

TcpSocket.cpp

#include "TcpSocket.h"TcpSocket::TcpSocket()
{_sock = _event.sock = INVALID_SOCKET;_event.event = this;_recvLen = 0;_bClose = false;
}TcpSocket::~TcpSocket()
{
}void TcpSocket::Init(EventLoop* loop)
{_loop = loop;_loop->AddEvent(&_event);
}void TcpSocket::OnAccept(SOCKET sock, SOCKADDR_IN* addr)
{_sock = sock;_event.sock = sock;memcpy(&_addr, addr, sizeof(addr));
}void TcpSocket::Close()
{if (_bClose) return;_bClose = true;_loop->DelEvent(&_event);
}void TcpSocket::OnNetEvent(E_Event_Type e)
{if (E_Event_Type::Recv == e){int nRecv = recv(_sock, _recvBuff + _recvLen, RECV_MAX_BUF - _recvLen, 0);if (nRecv <= 0){Close();return;}_recvLen += nRecv;while (_recvLen != 0){int nRet = OnNetMsg(_recvBuff, _recvLen);if (nRet <= 0)break;_recvLen -= nRet;for (int i = 0; i < _recvLen; ++i){_recvBuff[i] = _recvBuff[i + nRet];}}if (_recvLen == RECV_MAX_BUF) Close();}
}void TcpSocket::OnClose()
{closesocket(_sock);delete this;
}void TcpSocket::Send(const char* msg, int msgLen)
{send(_sock, msg, msgLen, 0);
}

EasyTcpServer.cpp

#define  _WINSOCK_DEPRECATED_NO_WARNINGS
#include <iostream>#include <WinSock2.h>
#pragma comment(lib,"ws2_32")
#include <vector>#include "TcpListen.h"
#include "TcpSocket.h"class EasyTcpClient :public TcpSocket
{
public:// 通过 TcpSocket 继承virtual int OnNetMsg(const char* const msg, int msgLen) override{std::cout << msgLen << "接受客户端数据:" << msg << std::endl;return msgLen;}
};class EasyTcpServer :public TcpListen
{
public:void OnAccpet(TcpSocket* sock) override{//sock->Init(_loop)sock->Init(_loop);std::cout << "客户端连接" << std::endl;}};int main()
{// 加载网络环境WSADATA wsaData;WSAStartup(MAKEWORD(2, 2), &wsaData);EventLoop loop;EasyTcpServer listen;listen.Init(&loop, []()->TcpSocket*{return new EasyTcpClient;});listen.Listen(7890);while (true){loop.LoopOnce();}return 0;
}

最后

void OnAccpet(TcpSocket* sock) override
{//sock->Init(_loop)sock->Init(_loop);std::cout << "客户端连接" << std::endl;
}

};

int main()
{
// 加载网络环境
WSADATA wsaData;
WSAStartup(MAKEWORD(2, 2), &wsaData);

EventLoop loop;EasyTcpServer listen;listen.Init(&loop, []()->TcpSocket*{return new EasyTcpClient;});listen.Listen(7890);while (true)
{loop.LoopOnce();
}return 0;

}

# 最后代码经供参考，如有疑问或者代码有问题欢迎提出