上一篇我们讲的TCP服务器的简单实现是只有一个进程连接的情况,但是实际上,这是不现实的,所以我们要改进我们的程序,使其可以服务于多个进程
直接上代码
server.c
#include <stdio.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
void processrequest(int client_sock,struct sockaddr* client_socket)
{
char buf[1024] = {0};
ssize_t s = read(client_sock,buf,sizeof(buf));
if(s < 0)
{
perror("read");
continue;
}
if(s == 0)
{
//说明对端关闭
printf("client %s say bye",inet_ntoa(client_socket->sin_addr));
close(client_sock);
break;
}
buf[s] = '\0';
printf("client:# %s",buf);
printf("please wait...\n");
write(client_sock,buf,sizeof(buf));
}
void createworker(int client_sock,struct sockaddr * client_socket)
{
printf("get a new connect\n");
pid_t pid = fork();
if(pid < 0)
{
printf("fork error\n");
return;
}
else if(pid == 0)
{
if(fork() == 0)
{
processrequest(client_sock,&client_socket);
}
exit(0);
}
else
{
waitpid(pid,NULL,0);
}
}
int main(int argc,char *argv[])
{
if(argv != 3)
{
printf("usage is ./server IP PORT\n");
return 1;
}
int sock = socket(AF_INET,SOCK_STREAM,0);
if(sock < 0)
{
printf("socket error\n");
close(sock);
return 2;
}
struct sockaddr_in server_socket;
bzero(&server_socket,sizeof(server_socket));
server_socket.sin_family = AF_INET;
server_socket.sin_port = htons(atoi(argv[2]));
server_socket.sin_addr.s_addr = inet_addr(argv[1]);
if(bind(sock,(struct sockaddr*)&server_socket,sizeof(struct sockaddr_in) < 0)
{
printf("bind error\n");
close(sock);
return 2;
}
if(listen(sock,_BACKLOG_) < 0)
{
printf("listen error\n");
close(sock);
return 3;
}
printf("bind and listen is success,please wait accept...\n");
while(1)
{
struct sockaddr_in client_socket;
socklen_t len = 0;
int client_sock = accept(sock,(struct sockaddr*)&client_socket,&len);
//int accept(int sockfd,struct sockaddr *addr,socklen_t *addrlen);
//addrlen参数是一个传入传出参数,传入的是调用者提供的,缓冲区addr的长度以避免缓冲区溢出问题,
//传出的是客户端地址结构体的实际长度(有可能没有占满调用者提供的缓冲区);
if(client_sock < 0)
{
printf("accept error\n");
close(sock);
return 4;
}
createworker(client_sock,&client_socket)//结构体client_socket传参用指针
}
}
client.c
#include <stdio.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <string.h>
#include <errno.h>
#include <netinet/in.h>
#include <arpa/inet.h>
int main(int argc,char *argv)
{
if(argc != 3)
{
printf("usage is ./client IP PORT");
return 1;
}
int sock = socket(AF_INET,SOCK_STREAM,0);
if(sock < 0)
{
perror("socket");
return 2;
}
struct sockaddr_in server_sock;
bzero(&server_sock,sizeof(server_sock));
server_sock.sin_family = AF_INET;
server_sock.sin_port = htons(argv[2]);
server_sock.sin_addr.s_addr = inet_addr(atoi(argv[1]));
int ret = connect(sock,(struct sockaddr*)&server_sock,sizeof(server_sock));
if(ret < 0)
{
perror("connect");
return 3;
}
pintf("connect is success!\n");
while(1)
{
char buf[1024] = {0};
printf("client #:");
fflush(0);
read(0,buf,strlen(buf));
buf[strlen(buf)-1] = '\0';
write(sock,buf,strlen(buf));
if(strncasecmp(buf,"quit",4) == 0);
{
printf("client quit\n");
break;
}
printf("please wait...\n");
read(sock,buf,sizeof(buf));
printf("server $:%s\n");
}
close(sock);
return 0;
}