【文件属性】：
文件名称：tcp并发服务器代码
文件大小：4KB
文件格式：C
更新时间：2014-10-29 16:11:09
tcp
popen重写
/*
* =====================================================================================
*
* Filename: tcpserver.c
*
* Description: this program is demostrate to how to write a remote control server
*
* Version: 1.0
* Created: 2010年09月11日 21时28分21秒
* Revision: none
* Compiler: gcc
*
* Author: Gang Liang (cs.scu.edu.cn/~lianggang), lianggang@scu.edu.cn
* Company: Sichuan university
*
=====================================================================================
*/
#include
#include
#include
#include
#include
#include
#include
#include
#define PORT 8900
#define BUFSIZE 2048
#define SHELL "/bin/sh"
FILE *myPopen(char *command,char *type)
{
int f_des[2];
int pid_t;
// pipe(f_des);
if((type[0]!='r'&&type[0]!='w')||type[1]!=0)
{
printf("myPopen()flag error/n");
return NULL;
}
if(pipe(f_des)==-1)
{
printf("pipe create error/n");
return NULL;
}
pid_t=fork();
if(pid_t<0)
return NULL;
if(pid_t==0)
{
if(type[0]=='r')
{
close(f_des[0]);
dup2(f_des[1],STDOUT_FILENO);
close(f_des[1]);
}
else{
close(f_des[1]);
dup2(f_des[0],STDIN_FILENO);
close(f_des[0]);
}
execl(SHELL,"sh","-c",command,(char*)0);
_exit(127);
char *argv[] = {command,0};
if(execvp(command,argv)==-1)
return NULL;
}
wait(0);
if(type[0]=='r')
{
close(f_des[1]);
return fdopen(f_des[0],"r");
}
else{
close(f_des[0]);
return fdopen(f_des[1],"w");
}
}
int execute(char*command,char*buf)
{
FILE *fp;
int count;
char commandbuf[2056];
if ((NULL==command)||(NULL==buf))
{
perror("command or buf is empty\n");
return -1;
}
count =0;
memset(commandbuf,0,2056);
strcat(commandbuf,"sh -c ");
strcat(commandbuf,command);
fprintf(stderr,"the command is %s\n",commandbuf);
if (NULL==(fp=myPopen(commandbuf,"r")))
{
perror("create pipe error\n");
return -1;
}
while ((count<2047) && (EOF!=(buf[count++]=fgetc(fp))));
buf[count-1]='\0';
return count;
}
int main()
{
int sockfd;
int conn_sock;
char sendbuf[BUFSIZE];
char recvbuf[BUFSIZE];
int sendnum;
int recvnum;
int length;
struct sockaddr_in client;
struct sockaddr_in server;
int opt;
int cnt;
pid_t pid;
/* The first stage:INITILIZE */
memset(&client,0,sizeof(client));
memset(&server,0,sizeof(server));
memset(sendbuf,0,BUFSIZE);
memset(recvbuf,0,BUFSIZE);
length=0;
sockfd=-1;
conn_sock=-1;
opt=SO_REUSEADDR;
/*The second stage:create listen socket */
if (-1==(sockfd=socket(AF_INET,SOCK_STREAM,0)))
{
perror("create socket error\n");
return -1;
}
setsockopt(sockfd,SOL_SOCKET,SO_REUSEADDR,&opt,sizeof(opt));
/* The third stage:bind socket */
server.sin_family=AF_INET;
server.sin_addr.s_addr=htonl(INADDR_ANY);
server.sin_port=htons(PORT);
if (-1==bind(sockfd,(struct sockaddr*)&server,sizeof(server)))
{
perror("bind socket error\n");
close(sockfd);
return -1;
}
/* The fourth stage:listen socket */
if (-1==listen(sockfd,10))
{
perror("listen socket error\n");
close(sockfd);
return -1;
}
/* The fifth stage:creat connect socket */
while(1)
{
if (-1==(conn_sock=accept(sockfd,(struct sockaddr*)&client,&length)))
{
perror("three shakehands error\n");
close(sockfd);
return -1;
}
/* the commnication with client */
pid=fork();
if(pid==0)
{
close(sockfd);
while(1)
{
memset(recvbuf,0,BUFSIZE);
memset(sendbuf,0,BUFSIZE);
if (0>=(recvnum=read(conn_sock,recvbuf,BUFSIZE)))
{
perror("the commucation error\n");
close(conn_sock);
close(sockfd);
return -1;
}
recvbuf[recvnum]='\0';
fprintf(stderr,"the command is:%s\n",recvbuf);
if (0==strcmp(recvbuf,"quit"))
{
fprintf(stderr,"the client is quit\n");
close(conn_sock);
break;
}
if (1>=(cnt=execute(recvbuf,sendbuf)))
{
sprintf(sendbuf,"the invalid command,please try again\n");
}
fprintf(stderr,"the result is \n%s",sendbuf);
if (0>=(sendnum=write(conn_sock,sendbuf,strlen(sendbuf))))
{
perror("the commucation error\n");
close(sockfd);
close(conn_sock);
return -1;
}
}
}
else if(pid>0)
{
close(conn_sock);
continue;
}
}
close(sockfd);
}
