day37:网编day4，多点通信和并发服务器

一、广播接收方：

#include <myhead.h>#define ERR_MSG(msg) do{\
fprintf(stderr,"__%d__\n",__LINE__);\
perror(msg);\
}while(0)#define BRD_IP "192.168.114.255"
#define BRD_PORT 8888int main(int argc, const char *argv[])
{//创建报式套接字int sfd = -1;if((sfd = socket(AF_INET,SOCK_DGRAM,0)) < 0){ERR_MSG("socket");}printf("socket success sfd=%d\n",sfd);//填充地址信息结构体给bind用struct sockaddr_in sin;sin.sin_family = AF_INET; 	//必须填AF_INETsin.sin_port = htons(BRD_PORT); 	//广播端口号sin.sin_addr.s_addr = inet_addr(BRD_IP); 	//广播IP//bind绑定地址信息if(bind(sfd,(struct sockaddr*)&sin,sizeof(sin)) < 0){ERR_MSG("bind");return -1;}printf("bind success[%s:%d]\n",BRD_IP,BRD_PORT);socklen_t addrlen = sizeof(sin);char buf[128]="";ssize_t len;while(1){if((len = recvfrom(sfd,buf,sizeof(buf),0,(struct sockaddr*)&sin,&addrlen)) < 0){ERR_MSG("recvfrom");return -1;}printf("recvfrom success %s\n",buf);}close(sfd);return 0;
}

二、广播发送方：

#include <myhead.h>#define ERR_MSG(msg) do{\
fprintf(stderr,"__%d__\n",__LINE__);\
perror(msg);\
}while(0)#define BRD_IP "192.168.114.255"
#define BRD_PORT 8888int main(int argc, const char *argv[])
{//创建报式套接字int cfd = -1;if((cfd = socket(AF_INET,SOCK_DGRAM,0)) < 0){ERR_MSG("socket");}printf("socket success cfd=%d\n",cfd);int broad = 1;if(setsockopt(cfd,SOL_SOCKET,SO_BROADCAST,(int*)&broad,sizeof(broad)) < 0){ERR_MSG("setsockpot");return-1;}printf("setsockpot success\n");//非必须绑定//填充地址信息结构体给sendtostruct sockaddr_in sin;sin.sin_family = AF_INET; 	//必须填AF_INETsin.sin_port = htons(BRD_PORT); 	//广播端口号sin.sin_addr.s_addr = inet_addr(BRD_IP); 	//广播IPprintf("bind success[%s:%d]\n",BRD_IP,BRD_PORT);char buf[128]="";ssize_t len;while(1){//清空bufbzero(buf,sizeof(buf));//从终端输入数据保存到buf中fscanf(stdin,"%s",buf);while(getchar()!=10);if(sendto(cfd,buf,strlen(buf),0,(struct sockaddr*)&sin,sizeof(sin)) < 0){ERR_MSG("sendto");return -1;}printf("sendto success\n");}close(cfd);return 0;
}

三、组播接收方：

#include <myhead.h>#define ERR_MSG(msg) do{\
fprintf(stderr,"__%d__\n",__LINE__);\
perror(msg);\
}while(0)#define GRP_IP "224.1.2.3" 	//组播IP
#define IP "192.168.114.94" //本机IP
#define GRP_PORT 8888int main(int argc, const char *argv[])
{//创建报式套接字int sfd = -1;if((sfd = socket(AF_INET,SOCK_DGRAM,0)) < 0){ERR_MSG("socket");}printf("socket success sfd=%d\n",sfd);//填充结构体，来完成组播连接struct ip_mreqn grp;grp.imr_multiaddr.s_addr = inet_addr(GRP_IP); //组播IPgrp.imr_address.s_addr = inet_addr(IP); //本机IPgrp.imr_ifindex = 0; //自动//设置连接组播if(setsockopt(sfd,IPPROTO_IP,IP_ADD_MEMBERSHIP,&grp,sizeof(grp)) < 0){ERR_MSG("setsockopt");return -1;}printf("setsockopt success\n");//填充地址信息结构体给bind用struct sockaddr_in sin;sin.sin_family = AF_INET; 	//必须填AF_INETsin.sin_port = htons(GRP_PORT); 	//组播端口号sin.sin_addr.s_addr = inet_addr(GRP_IP); 	//组播IP//bind绑定地址信息if(bind(sfd,(struct sockaddr*)&sin,sizeof(sin)) < 0){ERR_MSG("bind");return -1;}printf("bind success[%s:%d]\n",GRP_IP,GRP_PORT);socklen_t addrlen = sizeof(sin);char buf[128]="";ssize_t len;while(1){if((len = recvfrom(sfd,buf,sizeof(buf),0,(struct sockaddr*)&sin,&addrlen)) < 0){ERR_MSG("recvfrom");return -1;}printf("recvfrom success %s\n",buf);}close(sfd);return 0;
}

四、组播发送方：

#include <myhead.h>#define ERR_MSG(msg) do{\
fprintf(stderr,"__%d__\n",__LINE__);\
perror(msg);\
}while(0)#define BRD_IP "224.1.2.3"
#define BRD_PORT 8888int main(int argc, const char *argv[])
{//创建报式套接字int cfd = -1;if((cfd = socket(AF_INET,SOCK_DGRAM,0)) < 0){ERR_MSG("socket");}printf("socket success cfd=%d\n",cfd);int broad = 1;if(setsockopt(cfd,SOL_SOCKET,SO_BROADCAST,(int*)&broad,sizeof(broad)) < 0){ERR_MSG("setsockpot");return-1;}printf("setsockpot success\n");//非必须绑定//填充地址信息结构体给sendtostruct sockaddr_in sin;sin.sin_family = AF_INET; 	//必须填AF_INETsin.sin_port = htons(BRD_PORT); 	//广播端口号sin.sin_addr.s_addr = inet_addr(BRD_IP); 	//广播IPprintf("bind success[%s:%d]\n",BRD_IP,BRD_PORT);char buf[128]="";ssize_t len;while(1){//清空bufbzero(buf,sizeof(buf));//从终端输入数据保存到buf中fscanf(stdin,"%s",buf);while(getchar()!=10);if(sendto(cfd,buf,strlen(buf),0,(struct sockaddr*)&sin,sizeof(sin)) < 0){ERR_MSG("sendto");return -1;}printf("sendto success\n");}close(cfd);return 0;
}

五、TCP多线程并发服务器：

#include <myhead.h>#define ERR_MSG(msg) do{\fprintf(stderr,"__%d__\n",__LINE__);\perror(msg);\
}while(0)#define IP "192.168.114.94"
#define PORT 8888int del_cli_msg(int newfd,struct sockaddr_in cin);
void handler(int num)
{if(num == SIGCHLD){while(waitpid(-1,NULL,WNOHANG) > 0);}
}
int main(int argc, const char *argv[])
{if(signal(SIGCHLD,handler) == SIG_ERR){ERR_MSG("signal");return -1;}printf("signal success\n");//创建流式套接字int sfd = -1;if((sfd = socket(AF_INET,SOCK_STREAM,0)) < 0){ERR_MSG("socket");return -1;}printf("socket success sfd = %d\n",sfd);//允许端口快速的被复用int reuse = 1;                                                            if(setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) < 0){ERR_MSG("setsockopt");return -1;}printf("允许端口快速的被复用成功\n");	//填充地址信息结构体给bind使用struct sockaddr_in sin;sin.sin_family = AF_INET;sin.sin_port = htons(PORT); 	//服务器端口号sin.sin_addr.s_addr = inet_addr(IP); 	//服务器IP//bind必须绑定IP和端口号if(bind(sfd,(struct sockaddr*)&sin,sizeof(sin)) < 0){ERR_MSG("bind");return -1;}printf("bind success [%s:%d]\n",IP,PORT);//listen把sfd切换成监听模式if(listen(sfd,128) < 0){ERR_MSG("listen");return -1;}printf("listen success sfd = %d\n",sfd);struct sockaddr_in cin;socklen_t addrlen=sizeof(cin);int newfd =-1;pid_t pid;while(1){//accept接收客户端发送过来的地址信息，创建一个newfd与其通讯accept//父进程专门负责连接if((newfd = accept(sfd,(struct sockaddr*)&cin,&addrlen)) < 0){ERR_MSG("accept");return -1;}printf("[%s:%d]客户端连接成功 newfd = %d\n",\inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),newfd);pid = fork();if(0 == pid){close(sfd);//子进程专门负责交互del_cli_msg(newfd,sin);exit(0);}close(newfd);}close(sfd);return 0;
}
int del_cli_msg(int newfd,struct sockaddr_in cin)
{char buf[128] ="";ssize_t len = 0;while(1){bzero(buf,sizeof(buf));len = recv(newfd,buf,sizeof(buf),0);if(len< 0){ERR_MSG("recvfrom");return -1;}else if(len == 0){printf("[%s:%d]客户端已下线 newfd = %d\n",\inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),newfd);break;}printf("recv success [%s:%d],newfd=%d buf=%s\n",\inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),newfd,buf);/*bzero(buf,sizeof(buf));printf("请输入数据发送给客户端");fscanf(stdin,"%s",buf);while(getchar()!=10);*/strcat(buf,">-<");if(send(newfd,buf,strlen(buf),0) < 0){ERR_MSG("send");return -1;}printf("send success buf = %s\n",buf);}
}

六、TCP多线程并发服务器：

#include <myhead.h>#define ERR_MSG(msg) do{\fprintf(stderr,"__%d__\n",__LINE__);\perror(msg);\
}while(0)#define IP "192.168.114.94"
#define PORT 8888
struct Data
{int newfd;struct sockaddr_in cin;
};
void *del_cli_msg(void *arg);
int main(int argc, const char *argv[])
{printf("signal success\n");//创建流式套接字int sfd = -1;if((sfd = socket(AF_INET,SOCK_STREAM,0)) < 0){ERR_MSG("socket");return -1;}printf("socket success sfd = %d\n",sfd);//允许端口快速的被复用int reuse = 1;                                                            if(setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) < 0){ERR_MSG("setsockopt");return -1;}printf("允许端口快速的被复用成功\n");	//填充地址信息结构体给bind使用struct sockaddr_in sin;sin.sin_family = AF_INET;sin.sin_port = htons(PORT); 	//服务器端口号sin.sin_addr.s_addr = inet_addr(IP); 	//服务器IP//bind必须绑定IP和端口号if(bind(sfd,(struct sockaddr*)&sin,sizeof(sin)) < 0){ERR_MSG("bind");return -1;}printf("bind success [%s:%d]\n",IP,PORT);//listen把sfd切换成监听模式if(listen(sfd,128) < 0){ERR_MSG("listen");return -1;}printf("listen success sfd = %d\n",sfd);struct sockaddr_in cin;socklen_t addrlen=sizeof(cin);int newfd =-1;pthread_t tid;while(1){//accept接收客户端发送过来的地址信息，创建一个newfd与其通讯accept//父进程专门负责连接if((newfd = accept(sfd,(struct sockaddr*)&cin,&addrlen)) < 0){ERR_MSG("accept");return -1;}printf("[%s:%d]客户端连接成功 newfd = %d\n",\inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),newfd);struct Data data;data.newfd = newfd;data.cin = cin;if(pthread_create(&tid,NULL,del_cli_msg,&data)){printf("pthread_create error\n");return -1;}printf("create success\n");pthread_detach(tid);}close(sfd);return 0;
}
void *del_cli_msg(void *arg)
{int newfd = ((struct Data*)arg)->newfd;struct sockaddr_in cin = ((struct Data*)arg)->cin;char buf[128] ="";ssize_t len = 0;while(1){bzero(buf,sizeof(buf));len = recv(newfd,buf,sizeof(buf),0);if(len< 0){ERR_MSG("recvfrom");break;}else if(len == 0){printf("[%s:%d]客户端已下线 newfd = %d\n",\inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),newfd);break;}printf("recv success [%s:%d],newfd=%d buf=%s\n",\inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),newfd,buf);/*bzero(buf,sizeof(buf));printf("请输入数据发送给客户端");fscanf(stdin,"%s",buf);while(getchar()!=10);*/strcat(buf,">-<");if(send(newfd,buf,strlen(buf),0) < 0){ERR_MSG("send");break;}//printf("send success buf = %s\n",buf);}
}

七、多线程并发服务器为什么不能将newfd定义成全局？

不能，因为如果newfd设成全局变量，而多线程之间共享0-3G用户空间，临界资源，所以会导致newfd变化后，原先线程进行交互。

八、基于UDP的TFTP文件传输，完成下载和上传功能，制作的是客户端，与tftp服务器进行交互

#include <myhead.h>#define ERR(s) do\
{\fprintf(stderr,"__%d__",__LINE__);\perror(s);\
}while(0)
#define PORT 69
#define IP "192.168.114.103"int do_download(int cfd,struct sockaddr_in sin);
int do_upload(int cfd,struct sockaddr_in sin);
int main(int argc, const char *argv[])
{//创建报式套接字socketint cfd;if((cfd = socket(AF_INET,SOCK_DGRAM,0)) < 0){ERR("socket");return -1;}printf("socket success\n");struct sockaddr_in sin;sin.sin_family = AF_INET;sin.sin_port = htons(PORT);sin.sin_addr.s_addr = inet_addr(IP);char choose = 0;while(1){system("clear");printf("--------------------------------\n");printf("-------------1下载--------------\n");printf("-------------2上传--------------\n");printf("-------------3退出--------------\n");printf("--------------------------------\n");printf("请输入>>>");scanf("%c",&choose);while(getchar()!=10); 	//吸收垃圾字符switch(choose){case '1':do_download(cfd,sin);break;case '2':do_upload(cfd,sin);break;case '3':goto END;break;default :printf("输入错误，请重新输入\n");}printf("请输入任意字符清屏\n");while(getchar()!=10);}
END://关闭套接字close(cfd);return 0;
}int do_download(int cfd,struct sockaddr_in sin)
{/*//组下载请求包char buf[516] = "";char f_n[20] = "";//操作码unsigned short *ptr1 = (unsigned short*)buf;*ptr1 = htons(1); 	//组操作码//文件名char *ptr2 = (char *)(ptr1+1);strcpy(ptr2,f_n);//模式char *ptr3 = ptr2 + strlen(f_n) + 1;strcpy(ptr3,"octet");int size = 2+strlen(ptr2)+1+strlen(ptr3)+1;*/char buf[516] = "";char f_n[20] = "";int num=1;printf("请输入文件名>>> ");//终端输入要下载的文件名fgets(f_n,sizeof(f_n),stdin);f_n[strlen(f_n)-1] = '\0';int fd;if((fd = open(f_n,O_RDONLY|O_CREAT|O_TRUNC,0664)) == -1){ERR("open");return -1;}//用sprintf拼接int size = sprintf(buf,"%c%c%s%c%s%c",0,1,f_n,0,"octet",0);//发送下载请求sendtoif(sendto(cfd,buf,size,0,(struct sockaddr*)&sin,sizeof(sin)) < 0 ){ERR("sendto askpackage");return -1;}printf("sendto askpackage success\n");ssize_t len = -1;struct sockaddr_in addrin;socklen_t addrlen=sizeof(addrin);while(1){//清空bufbzero(buf,sizeof(buf));//接收数据recvfrom，接收地址信息if((len = recvfrom(cfd,buf,sizeof(buf),0,(struct sockaddr*)&addrin,&addrlen)) < 0){ERR("recvfrom datapackage");return -1;}unsigned short ptr2=ntohs(*(unsigned short*)(buf+2));printf("%hu\n",ptr2);	//当操作码为5时if(5 == buf[1]){fprintf(stderr, "错误码：%d，错误信息：%s\n", ntohs(*(unsigned short*)(buf+2)), buf+4);			break;}//当操作码为3,并且块编号正确时else if(3 == buf[1] && num == ptr2){printf("%d\n",fd);//跳过前四个字节，写入文件if(write(fd,buf+4,len-4)<0){ERR("write");return -1;}//组ACK包buf[1] = 4;	//发送ACK包，sendtoif(sendto(cfd,buf,4,0,(struct sockaddr*)&addrin,addrlen) < 0){ERR("sendto ACKpackage");return -1;}num++;//判断数据是否小于512个字节，若小于则下载完成if(len < 516){printf("download success\n");break;}}}close(fd);return 0;
}int do_upload(int cfd,struct sockaddr_in sin)
{char f_n[20]="";printf("请输入传输文件名>>>");fscanf(stdin,"%s",f_n);while(getchar()!=10);//打开文件int srcfd = -1;if((srcfd = open(f_n,O_RDONLY)) < 0){if(errno == ENOENT){printf("文件不存在，请重新输入>>>");return -2;}else{ERR("open srcfile");return -1;}}char buf[516]="";//用sprintf拼接读写请求封包int size=sprintf(buf,"%c%c%s%c%s%c",0,2,f_n,0,"octet",0);if(sendto(cfd,buf,size,0,(struct sockaddr*)&sin,sizeof(sin)) < 0){ERR("sendto askpackage");return -1;}printf("sendto askpackage success\n");//记录块编号int num=0;unsigned short* ptr = (unsigned short *)(buf+2);//记录我要传过去数据的大小ssize_t len = -1;socklen_t addrlen = sizeof(sin);while(1){bzero(buf,sizeof(buf));//接受ACKif(recvfrom(cfd,buf,sizeof(buf),0,(struct sockaddr*)&sin,&addrlen) < 0){ERR("recvfrom ACKpackage");return -1;}printf("recvfrom ACKpackage success\n");//当传过来的是ACK并且对应的块编号是需要的块编号时if(buf[1] == 4){if(*ptr == htons(num)){num++;//把操作码改为3，向服务器发送数据buf[1] = 3;//*(unsigned short *)(buf+2)= htons(num);*ptr = htons(num);//从文件中读取数据，保存到buf中len = read(srcfd,buf+4,sizeof(buf)-4);if(len < 0){ERR("read srcfd");return -1;}else if(0 == len){printf("文件上传完毕\n");break;}//向服务器发送打包好的数据包if(sendto(cfd,buf,len+4,0,(struct sockaddr*)&sin,addrlen) < 0){ERR("sendto datapackage");return -1;}printf("sendto datapackage success\n");}else{printf("网络不好，上传数据失败\n");break;}}else if(buf[1] == 5){fprintf(stderr,"错误码：%d，错误信息：%s\n",\ntohs(*(unsigned short*)(buf+2)),buf+4);break;}}return 0;
}