socket编程实现TCP通信

tcp_client.cc

#include <iostream>
#include <cstring>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <pthread.h>
#include <unistd.h>
#include <cerrno>
#include "log.hpp"
#define SIZE 1024
uint16_t serverport;
std::string serverip;
void *tcpSend(void *args)
{int sock = *(int *)args;std::string message;while (true){std::cerr << "请输入你的信息# ";std::getline(std::cin, message);send(sock, message.c_str(), message.size(), 0);}
}void *tcpRecv(void *args)
{int sock = *(int *)args;char buff[1024];while (true){ssize_t s = recv(sock, buff, sizeof(buff) - 1, 0);if (s > 0){buff[s] = '\0';printf("%s\n", buff);fflush(stdout);}}
}
int main(int argc, char *argv[])
{if (argc != 3){std::cout << "Usage: " << argv[0] << " ip port" << std::endl;exit(1);}int sock = socket(AF_INET, SOCK_STREAM, 0);if (sock < 0){std::cerr << "FATAL " << errno << ":" << strerror(errno);exit(2);}serverport = atoi(argv[2]);serverip = argv[1];struct sockaddr_in server;memset(&server, 0, sizeof server);server.sin_family = AF_INET;server.sin_port = htons(serverport);server.sin_addr.s_addr = inet_addr(serverip.c_str());if (connect(sock, (struct sockaddr*)&server, sizeof(server)) == -1) {printf("连接失败 [%d:%s]\n",errno,strerror(errno));close(sock);exit(1);}LogMessage(NORMAL,"connect success");pthread_t t1, t2;pthread_create(&t1, nullptr, tcpSend, (void *)&sock);pthread_create(&t2, nullptr, tcpRecv, (void *)&sock);pthread_join(t1, nullptr);pthread_join(t2, nullptr);close(sock);return 0;
}

tcp_server.cc

#include "tcp_server.hpp"
int main(int argc,char* argv[])
{if(argc != 2){std::cout<<"Usage: "<<argv[0]<<" port"<<std::endl;exit(1);}uint16_t port = atoi(argv[1]);TcpServer* svr = new TcpServer(port);svr->initServer();svr->start();delete svr;return 0;
}

tcp_server.hpp

#ifndef UDP_SERVER_HPP
#define UDP_SERVER_HPP#include <iostream>
#include <cstring>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unordered_map>
#include <unistd.h>
#include <signal.h>
#include <wait.h>
#include "log.hpp"#define SIZE 1024static void service(int sock, std::string &client_ip, uint16_t &client_port)
{char buff[1024];while (true){ssize_t s = read(sock, buff, sizeof(buff) - 1);if (s > 0){buff[s] = '\0';printf("[%s:%d]# %s\n", client_ip.c_str(), client_port, buff);}else if (s == 0){LogMessage(NORMAL, "[%s:%d] shutdown, me too!", client_ip.c_str(), client_port);break;}else{LogMessage(ERROR, "read socket error, %d:%s", errno, strerror(errno));break;}write(sock, buff, strlen(buff));}
}
struct ThreadData
{int _sock;std::string _ip;uint16_t _port;
};
class TcpServer
{
private:const int gbacklog = 20;public:static void* threadRoutine(void* args){pthread_detach(pthread_self());ThreadData* td = (ThreadData*)args;service(td->_sock, td->_ip, td->_port);delete td;return nullptr;}TcpServer(uint16_t port, std::string ip = "0.0.0.0"): _port(port), _listensock(-1),_ip(ip){}void initServer(){// 创建套接字_listensock = socket(AF_INET, SOCK_STREAM, 0);if (_listensock < 0){LogMessage(FATAL, "socket error, %d:%s", errno, strerror(errno));exit(2);}// 绑定struct sockaddr_in local;local.sin_family = AF_INET;local.sin_port = htons(_port);local.sin_addr.s_addr = inet_addr(_ip.c_str());if (bind(_listensock, (struct sockaddr *)&local, sizeof(local)) < 0){LogMessage(FATAL, "bind error, %d:%s", errno, strerror(errno));exit(3);}// 建立连接(监听)if (listen(_listensock, gbacklog) < 0){LogMessage(FATAL, "listen error, %d:%s", errno, strerror(errno));exit(4);}LogMessage(NORMAL, "init TCP server success, listensock: %d", _listensock);}void start(){signal(SIGCHLD,SIG_IGN);//不理会子进程 v2.1while (true){// 获取连接struct sockaddr_in src;socklen_t len = sizeof(src);int servicesock = accept(_listensock, (struct sockaddr *)&src, &len);std::cout<<servicesock<<std::endl;if (servicesock < 0){LogMessage(ERROR, "accept error, %d:%s", errno, strerror(errno));continue;}uint16_t client_port = ntohs(src.sin_port);std::string client_ip = inet_ntoa(src.sin_addr);LogMessage(NORMAL, "link success, [%s:%d]", client_ip.c_str(), client_port);// 获取连接成功，开始通信服务// v1 单进程循环//service(servicesock, client_ip, client_port);//v2.0 多进程// pid_t id = fork();// if(id == 0)// {//     close(_listensock);//     service(servicesock, client_ip, client_port);//     exit(0);// }// close(servicesock);//v2.1 多进程// pid_t id = fork();// if(id == 0)// {//     close(_listensock);//     if(fork() > 0) exit(0);//     service(servicesock, client_ip, client_port);// }// waitpid(id,nullptr,0);// close(servicesock);//v3 多线程ThreadData* td = new ThreadData;td->_sock = servicesock;td->_ip = client_ip;td->_port = client_port;pthread_t tid;pthread_create(&tid,nullptr,threadRoutine,(void*)td);close(servicesock);}}private:uint16_t _port;std::string _ip;int _listensock;
};
#endif

log.hpp

#pragma once
#include<iostream>
#include<cstdio>
#include<cstdarg>
#include<ctime>
#include<string>#define DEBUG   0
#define NORMAL  1
#define WARNING 2
#define ERROR   3
#define FATAL   4
const char* gLevelMap[]={"DEBUG","NORMAL","WARNING","ERROR","FATAL"};void LogMessage(int level,const char* format,...)
{char stdBuffer[1024] = {'\0'};time_t timestamp = time(nullptr);snprintf(stdBuffer,sizeof stdBuffer,"[%s] [%ld]",gLevelMap[level],timestamp);char logBuffer[1024] = {'\0'};;va_list args;va_start(args,format);vsnprintf(logBuffer,sizeof logBuffer,format,args);va_end(args);printf("%s%s\n",stdBuffer,logBuffer);
}

makefile

.PHONY:add
all:tcp_client tcp_server
tcp_client:tcp_client.ccg++ -o $@ $^ -std=c++11 -l pthread
tcp_server:tcp_server.ccg++ -o $@ $^ -std=c++11 -l pthread
.PHONY:clean
clean:rm -f tcp_client tcp_server