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我一直在努力编写一些套接字编程在Linux中，我试图做一个并发代理服务器。基本上我希望连接到代理服务器的每个客户端遇到2个问题。第一个是介绍命运的IP，第二个是它的端口号。在发送这些信息之后，代理服务器将把每个客户端连接到他们选择的IP（这是和回显服务器）。C Linux的tcp代理服务器套接字
我的问题是如何以及将在哪里保存每个用户回答的2个问题，然后将它们连接到他们选择的回显服务器。
这里的，我认为我们必须在工作的部分代码：
/*============ WARNS THAT SERVER IS READY TO ACCEPT REQUESTS ==================*/
if(listen(sockfd,5)==-1) Abort("Impossible to accept requests");
/*========== STARTS ANSWERING CLIENTS BY CONCURRENT FORM =============*/
cliaddr_len=sizeof(cli_addr);
while(1){
FD_ZERO(&fd_read);
FD_SET(STDIN_FILENO, &fd_read);
FD_SET(sockfd, &fd_read);
fflush(stdin);
n=select(32, &fd_read, NULL, NULL, NULL);
if(n<0)
if(errno!=EINTR){
close(sockfd);
Abort("Error on select");
}else
continue;
if(FD_ISSET(STDIN_FILENO, &fd_read)){
gets(comando);
if(strcmp(comand, "exit")==0){
close(sockfd);
printf("Goodbye...\n");
exit(0);
}
}
if(FD_ISSET(sockfd, &fd_read))
if((newsockfd=accept(sockfd,(struct sockaddr *)&cli_addr,&cliaddr_len))
==-1)
fprintf(stderr,"<SERV>Impossible to accept clients...\n");
else{
switch(fork()){/*Goes to backgroud*/
case -1:fprintf(stderr,"Impossible to answer...");
close(newsockfd);
break;
case 0:close(sockfd); /* SON */
AnswerClient(newsockfd);
exit(EXIT_SUCCESS);
default:close(newsockfd); /* DAD */
}
}
}
}
/*___________________________ AnswerClient ____________________________________
______________________________________________________________________________*/
void AnswerClient(int sockfd){
static char buffer[BUFFERSIZE];
static unsigned int cont=0U;
int nbytes;
pid_t pid=getpid();
while(1){
/*==================== PROCESS REQUEST ==========================*/
cont++;
switch((nbytes=ReadLine(sockfd,buffer,BUFFERSIZE))){
case -1:fprintf(stderr,"Error receiving data...\n");
return;
case 0:fprintf(stderr,"Client didnt sent data...\n");
return;
default:printf("\n<%d>Message received: %s\n",pid,buffer);
if(!strncmp(buffer,"exit",4)){
printf("<%d>Going shutdown...\n",pid);
close(sockfd);
return;
}
/*============ Sends Confirmation =============*/
sprintf(buffer,"<%d>",pid);
nbytes=strlen(buffer);
if(WriteN(sockfd,buffer,nbytes)!=nbytes)
fprintf(stderr,"Impossible to confirm.\n");
}
}
}
/*_____________________________ ReadLine _______________________________________
Reads a line (until find the caracter '\n') of a socket.
Returns:
-1 : if error
0 : EOF
!= : if read some bytes
______________________________________________________________________________*/
int ReadLine(int sockfd,char* buffer,int maxlen){
int n,rc;
char c;
for(n=0;n<maxlen-1;n++){
if((rc=read(sockfd,&c,1))==1){
*buffer++=c;
if(c=='\n') break;
}else if (rc==0) {
if(n==0) return(0); /*EOF*/
else break; /*EOF but has already read some bytes*/
} else return(-1); /*Error*/
}
*buffer=0;
return(n);
}
/*______________________________ WriteN _______________________________________
Writes n bytes on socket in case. Returns the number of bytes writen.
______________________________________________________________________________*/
int WriteN(int sockfd,char * buffer,int nbytes){
int nleft,nwritten;
nleft=nbytes;
while(nleft>0){
if((nwritten=write(sockfd,buffer,nleft))<=0) return(nwritten);
nleft-=nwritten;
buffer+=nwritten;
}
return(nbytes-nleft);
}
void Abort(char *msg){
fprintf(stderr,"\a<SER1>Fatal error: <%s>\n",msg);
perror("Erro do sistema");
exit(EXIT_FAILURE);
}
void buryZombie()
{
static int status;
wait(&status);
}
可有人请给我一个提示或只是告诉我正确的方法是什么？
RicardoCosta