2023.4.24

//TCP的select服务器

#include <string.h>
#include <stdio.h>
#include <stdlib.h>  
#include <sys/types.h>        
#include <sys/socket.h>    
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <unistd.h>
#include <arpa/inet.h>
#include<sys/wait.h>
#include<signal.h>
#include<sys/select.h>
#include<sys/time.h>
 
#define IP "192.168.0.116"
#define PORT 8888
#define ERR_MSG(msg) do{\
	fprintf(stderr,"line:%d\n",__LINE__);\
	perror(msg);\
}while(0)
 
int main(int argc, const char *argv[])
{
	//创建套接字：socket
	int sfd = socket(AF_INET,SOCK_STREAM,0);
	if(sfd < 0)
	{
		ERR_MSG("socket");
		return -1;
	}
 
	//允许端口快速被重复使用,当检测到该端口号没有被进程正常占用时候
	int reuse = 1;
	if(setsockopt(sfd,SOL_SOCKET,SO_REUSEADDR,&reuse,sizeof(reuse)) < 0)
	{
		ERR_MSG("setsockopt");
		return -1;
	}
	printf("允许端口快速重用\n");
	
	//填充服务器的地址信息结构体	
	struct sockaddr_in sin;
	sin.sin_family    =  AF_INET;
	sin.sin_port      =  htons(PORT);
	sin.sin_addr.s_addr = inet_addr(IP);
 
	//绑定服务器的IP和端口：必须绑定:bind
	if(bind(sfd,(struct sockaddr*)&sin,sizeof(sin)) < 0)
	{
		ERR_MSG("bind");
		return -1;
	}
	printf("bind success __%d__\n",__LINE__);
 
	//将套接字设置为被动监听状态:lieten
	if (listen(sfd, 128) < 0)
	{
		ERR_MSG("listen");
		return -1;
	}
	printf("listen success __%d__\n",__LINE__);
 
	fd_set readfds,tempfds;
 
	FD_ZERO(&readfds);    //清空集合
 
	//将需要的文件描述符添加到集合中去
	FD_SET(0,&readfds);
	FD_SET(sfd,&readfds);
 
	int maxfd = sfd;
 
	struct sockaddr_in saveCin[1024-4]; 	//另存连接成功的客户端的地址信息
 
	struct sockaddr_in cin; //储存连接成功的客户端信息
	socklen_t addrlen = sizeof(cin);
	int newfd = -1;
	char buf[128] = "";
	ssize_t res = 0;
	int s_res = 0;
 
	while(1)
	{
		tempfds = readfds;
		s_res = select(maxfd+1,&tempfds,NULL,NULL,NULL);
		if(s_res < 0)
		{
			ERR_MSG("select");
			return -1;
		}
		else if(0 == s_res)
		{
			printf("time out...\n");
			break;
		}
		printf("__%d__\n",__LINE__);
 
		for(int i = 0;i <= maxfd;i++)
		{
			if(FD_ISSET(i,&tempfds) == 0)   //i所代表的文件描述符不在集中
			{
				continue;
			}
			
			if(0 == i)
			{		
				printf("触发键盘输入事件>>>");
				fflush(stdout);
 
				int sndfd;
 
				res = scanf("%d %s",&sndfd,buf);
				while(getchar() != '\n');
				if(res != 0)
				{
					fprintf(stderr,"请输入正确格式：fd string\n");
					continue;
				}
 
				//若输入的sndfd非法，或者根本没有对应的客户端，则不发送
				if(sndfd <= sfd || sndfd >= 1024 || !FD_ISSET(sndfd,&readfds))
				{
					fprintf(stderr,"sndfd = %d 是非法的文件描述符\n",sndfd);
					continue;
				}
				if(send(sndfd,buf,sizeof(buf),0) < 0)
				{
					ERR_MSG("send");
					return -1;
				}
				printf("send to %d success\n",sndfd);
			}
			else if(sfd == i)
			{
				printf("触发客户端连接事件>>>");
				fflush(stdout);
 
				newfd = accept(sfd,(struct sockaddr*)&cin,&addrlen);
				if(newfd < 0)
				{
					ERR_MSG("accept");
					return -1;
				}
				printf("[%s : %d] newfd = %d 连接成功 __%d__\n",\
						inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),newfd,__LINE__);
 
				saveCin[newfd - 4] = cin;
 
				//将newfd添加到readfds集合中
				FD_SET(newfd,&readfds);
 
				//更新maxfd
				maxfd = maxfd > newfd?maxfd:newfd; 
 
			}
			else
			{
				fprintf(stderr,"触发客户端交互事件>>>");
				bzero(buf,sizeof(buf));
 
				//接收
				res = recv(i,buf,sizeof(buf),0);
				if(res < 0)
				{
					ERR_MSG("recv");
					return -1;
				}
				else if(0 ==res)
				{
					printf("[%s : %d] newfd = %d 客户端下线 __%d__\n",\
							inet_ntoa(saveCin[i-4].sin_addr),ntohs(saveCin[i-4].sin_port),i,__LINE__);
					//关闭文件描述符
					close(i);
 
					FD_CLR(i,&readfds);
 
					int j = maxfd;
					for( ; j > 0; j--);
					{
						if(FD_ISSET(j,&readfds))
						{
							break;
						}
					}
 
					maxfd = j;
 
					continue;
					
				}
 
				printf("[%s : %d] newfd = %d  %s__%d__\n",\
						inet_ntoa(saveCin[i-4].sin_addr),ntohs(saveCin[i-4].sin_port),i,buf,__LINE__);
 
					//发送
					strcat(buf,"*_*");
					if(send(i,buf,sizeof(buf),0) < 0)
					{
						ERR_MSG("send");
						return -1;
					}
					printf("发送成功\n");
				}
		}
	}
			
		//关闭文件描述符
		close(sfd);
		return 0;
 
}

TCP的poll客户端

#include <string.h>
#include <stdio.h>
#include <stdlib.h>  
#include <sys/types.h>        
#include <sys/socket.h>    
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <unistd.h>
#include <arpa/inet.h>
#include<sys/wait.h>
#include<signal.h>
#include<poll.h>
 
#define IP "192.168.0.116"
#define PORT 8888
 
#define ERR_MSG(msg) do{\
	fprintf(stderr,"line:%d\n",__LINE__);\
	perror(msg);\
}while(0)
 
 
int main(int argc, const char *argv[])
{
	//创建套接字：socket
	int sfd = socket(AF_INET,SOCK_STREAM,0);
	if(sfd < 0)
	{
		ERR_MSG("socket");
		return -1;
	}
 
	//填充服务器的地址信息结构体
	struct sockaddr_in sin;
	sin.sin_family    =  AF_INET;
	sin.sin_port      =  htons(PORT);
	sin.sin_addr.s_addr = inet_addr(IP);
 
 
	//连接服务器
	if(connect(sfd,(struct sockaddr*)&sin ,sizeof(sin)) < 0)
	{
		ERR_MSG("connect");
		return -1;
	}
	printf("connect success\n");
 
	struct pollfd fds[2]; 
 
	fds[0].fd = 0;  			
	fds[0].events = POLLIN; 	
 
	fds[1].fd = sfd; 			
	fds[1].events = POLLIN;
 
	char buf[128] = "";
	ssize_t res = 0;
	int p_res = -1;
 
	while(1)
	{
		p_res = poll(fds,2,-1);
		if(p_res < 0)
		{
			ERR_MSG("poll");
			return -1;
		}
		else if(0 == p_res)
		{
 
			printf("time out...\n");
			break;
		}
 
		if(fds[0].revents & POLLIN)
		{
			printf("触发键盘输入事件\n");
			bzero(buf,sizeof(buf));
			fgets(buf,sizeof(buf),stdin);
			buf[strlen(buf)-1] = '\0';
 
			//发送
			if(send(sfd,buf,sizeof(buf),0) < 0)
			{
				ERR_MSG("send");
				break;
			}
			printf("发送成功\n");
		}
 
		if(fds[1].revents &POLLIN)
		{
			printf("触发服务器交互事件\n");
		
			bzero(buf,sizeof(buf));
 
			//接收
			res = recv(sfd,buf,sizeof(buf),0);
			if(res < 0)
			{
				ERR_MSG("recv");
				return -1;
			}
			else if(0 == res)
			{
				printf("服务器下线\n");
				break;
			}
			printf(" : %s__%d__\n",buf,__LINE__);
 
		}
	}
	//关闭
	close(sfd);
	return 0;
}

//TCP的select客户端

#include <string.h>
#include <stdio.h>
#include <stdlib.h>  
#include <sys/types.h>        
#include <sys/socket.h>    
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <unistd.h>
#include <arpa/inet.h>
#include<sys/wait.h>
#include<signal.h>
#include<poll.h>
#include<sys/time.h>
#include<sys/select.h>
 
#define IP "192.168.0.116"
#define PORT 8888
 
#define ERR_MSG(msg) do{\
	fprintf(stderr,"line:%d\n",__LINE__);\
	perror(msg);\
}while(0)
 
 
int main(int argc, const char *argv[])
{
	//创建套接字：socket
	int sfd = socket(AF_INET,SOCK_STREAM,0);
	if(sfd < 0)
	{
		ERR_MSG("socket");
		return -1;
	}
 
	//填充服务器的地址信息结构体
	//该真实结构体根据地址制定
	struct sockaddr_in sin;
	sin.sin_family    =  AF_INET;
	sin.sin_port      =  htons(PORT);
	sin.sin_addr.s_addr = inet_addr(IP);
 
 
	//连接服务器
	if(connect(sfd,(struct sockaddr*)&sin ,sizeof(sin)) < 0)
	{
		ERR_MSG("connect");
		return -1;
	}
	printf("connect success\n");
 
	fd_set readfds,tempfds;
 
	FD_ZERO(&readfds);    //清空集合
	FD_ZERO(&tempfds);
 
	//将需要的文件描述符添加到集合中去
	FD_SET(0,&readfds);
	FD_SET(sfd,&readfds);
 
	int maxfd = sfd;
 
	struct sockaddr_in cin; //储存连接成功的客户端信息
	socklen_t addrlen = sizeof(cin);
	int newfd = -1;
	char buf[128] = "";
	ssize_t res = 0;
	int s_res = 0;
 
	while(1)
	{
		tempfds = readfds;
		s_res = select(maxfd+1,&tempfds,NULL,NULL,NULL);
		if(s_res < 0)
		{
			ERR_MSG("select");
			return -1;
		}
		else if(0 == s_res)
		{
			printf("time out...\n");
			break;
		}
		printf("__%d__\n",__LINE__);
	
		for(int i = 0;i <= maxfd;i++)
		{
			if(FD_ISSET(i,&tempfds) == 0)   
			{
				continue;
			}
 
			if(0 == i)
			{		
				//触发键盘输入事件
				bzero(buf,sizeof(buf));
				printf("请输入要发送的数据\n");
				fgets(buf,sizeof(buf),stdin);
				buf[strlen(buf)-1] = '\0';
				
				//发送
				if(send(sfd,buf,sizeof(buf),0) < 0)
				{
					ERR_MSG("send");
					break;
				}
				printf("发送成功\n");
			}
			else if(sfd == i)
			{
				bzero(buf,sizeof(buf));
 
				//接收
				res = recv(sfd,buf,sizeof(buf),0);
				if(res < 0)
				{
					ERR_MSG("recv");
					return -1;
				}
				else if(0 == res)
				{
					printf("服务器下线\n");
					break;
				}
			printf(" : %s__%d__\n",buf,__LINE__);
			}
 
		}
	}
	//关闭文件描述符
	close(sfd);
	return 0;
}