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chatserver.c
239 lines (182 loc) · 5.45 KB
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chatserver.c
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/*
$Id: chatserver.c,v 1.1 2005/09/24 09:48:53 ssim Exp $
$Log: chatserver.c,v $
Revision 1.1 2005/09/24 09:48:53 ssim
Initial revision
Revision 1.2 2003/10/13 14:11:53 sam
Added RCS tags
*/
#define __USE_BSD_SIGNAL
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <ctype.h>
#include <sys/ioctl.h>
#include <netinet/in.h>
#include <errno.h>
volatile int quit=0;
#define MAXCHAT 56
#define INBUFSIZE 1024
#define OUTBUFSIZE 65536
struct chat
{
int sock;
char inbuf[INBUFSIZE];
char obuf[OUTBUFSIZE];
int iptr,optr,in_len;
};
struct chat *chat;
void sig_leave(int dummy)
{
quit=1;
}
void kick_chat(int nr)
{
close(chat[nr].sock);
chat[nr].sock=0;
printf("kicked client %d\n",nr);
}
void new_chat(int sock)
{
int n,nsock,len=sizeof(struct sockaddr_in),one=1;
struct sockaddr_in addr;
nsock=accept(sock,(struct sockaddr *)&addr,&len);
if (nsock==-1) return;
ioctl(nsock,FIONBIO,(u_long*)&one); // non-blocking mode
for (n=1; n<MAXCHAT; n++) if (!chat[n].sock) break;
if (n==MAXCHAT) { close(nsock); return; }
bzero(chat+n,sizeof(struct chat));
chat[n].sock=nsock;
chat[n].in_len=0;
chat[n].iptr=0;
chat[n].optr=0;
printf("accepted new client %d\n",n);
}
void send_chat(int nr)
{
int ret,len;
char *ptr;
if (chat[nr].iptr<chat[nr].optr) {
len=OUTBUFSIZE-chat[nr].optr;
ptr=chat[nr].obuf+chat[nr].optr;
} else {
len=chat[nr].iptr-chat[nr].optr;
ptr=chat[nr].obuf+chat[nr].optr;
}
ret=send(chat[nr].sock,ptr,len,0);
if (ret==-1) { // send failure
kick_chat(nr);
return;
}
printf("sent %d bytes to client %d\n",ret,nr);
chat[nr].optr+=ret;
if (chat[nr].optr==OUTBUFSIZE) chat[nr].optr=0;
}
int internal_chat(unsigned char *buf,int len)
{
return 0; // ... !!!!!!!!!
}
int csend(int nr,unsigned char *buf,int len)
{
int tmp;
if (chat[nr].sock==0) return -1;
while (len) {
tmp=chat[nr].iptr+1;
if (tmp==OUTBUFSIZE) tmp=0;
if (tmp==chat[nr].optr) {
kick_chat(nr);
return -1;
}
chat[nr].obuf[chat[nr].iptr]=*buf++;
chat[nr].iptr=tmp;
len--;
}
return 0;
}
void rec_chat(int nr)
{
int len,n,channel;
len=recv(chat[nr].sock,(char*)chat[nr].inbuf+chat[nr].in_len,INBUFSIZE-chat[nr].in_len,0);
printf("received %d bytes from client %d\n",len,nr);
if (len<1) { // receive failure
//if (errno!=EWOULDBLOCK) {
kick_chat(nr);
//}
return;
}
chat[nr].in_len+=len;
while (chat[nr].in_len>1) {
len=*(unsigned short*)(chat[nr].inbuf)+2;
if (len>1000) {
kick_chat(nr);
return;
}
if (chat[nr].in_len>=len) {
channel=*(unsigned short*)(chat[nr].inbuf+2);
if (channel==1025) {
internal_chat(chat[nr].inbuf+4,len-4);
} else {
for (n=0; n<MAXCHAT; n++)
csend(n,chat[nr].inbuf,len);
}
chat[nr].in_len-=len;
if (chat[nr].in_len) memmove(chat[nr].inbuf,chat[nr].inbuf+len,chat[nr].in_len);
} else break;
}
}
int main(void)
{
int sock,one=1,fmax,cnt,n;
fd_set in_fd,out_fd;
struct sockaddr_in addr;
// ignore the silly pipe errors and hangups:
signal(SIGPIPE,SIG_IGN);
signal(SIGHUP,SIG_IGN);
// shutdown gracefully if possible:
signal(SIGQUIT,sig_leave);
signal(SIGINT,sig_leave);
signal(SIGTERM,sig_leave);
chat=calloc(MAXCHAT,sizeof(struct chat));
sock=socket(PF_INET,SOCK_STREAM,0);
if (sock==-1) return 0;
ioctl(sock,FIONBIO,(u_long*)&one); // non-blocking mode
setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(const char *)&one,sizeof(int));
addr.sin_family=AF_INET;
addr.sin_port=htons(5554);
addr.sin_addr.s_addr=0;
if (bind(sock,(struct sockaddr *)&addr,sizeof(addr))) return 0;
if (listen(sock,50)) return 0;
while (!quit) {
FD_ZERO(&in_fd); FD_ZERO(&out_fd); fmax=0;
FD_SET(sock,&in_fd);
if (sock>fmax) fmax=sock;
for (n=1; n<MAXCHAT; n++) {
if (chat[n].sock) {
if (chat[n].in_len<INBUFSIZE) {
FD_SET(chat[n].sock,&in_fd);
if (chat[n].sock>fmax) fmax=chat[n].sock;
}
if (chat[n].iptr!=chat[n].optr) {
FD_SET(chat[n].sock,&out_fd);
if (chat[n].sock>fmax) fmax=chat[n].sock;
}
}
}
cnt=select(fmax+1,&in_fd,&out_fd,NULL,NULL);
if (cnt<1) continue;
if (FD_ISSET(sock,&in_fd)) new_chat(sock);
for (n=1; n<MAXCHAT; n++) {
if (!chat[n].sock) continue;
if (FD_ISSET(chat[n].sock,&in_fd)) rec_chat(n);
if (FD_ISSET(chat[n].sock,&out_fd)) send_chat(n);
}
}
return 1;
}