#if HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <string.h>
#include <signal.h>

#include "pptpd.h"

#define	MFDSET(m,fd,fds)		\
	do { if( (fd) >= 0 )	{ FD_SET((fd),(fds)); m= m < (fd) ? (fd) : (m) ; } } while (0)

int loop( void )
{ int m, i = 1;
  struct control_struct *control = NULL,*c,**cc;
  struct ppp_struct *p,**pp;
  fd_set rds,wrs;
  struct timeval ntv;
  struct timeval tv;

  int s,a;
  int salen;
  struct sockaddr_in sa;
  int istimeout;
	if( (s=socket(PF_INET,SOCK_STREAM,0))<0 )
		return(-1);
	sa.sin_family = AF_INET;
	sa.sin_addr.s_addr=INADDR_ANY;
	sa.sin_port=htons(PPTP_PORT);
	setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &i, sizeof(i));
	if( bind(s,(struct sockaddr*)&sa,sizeof(struct sockaddr_in))<0 )
	{	close(s);
		return(-2);
	}
	listen(s, 8);
	gettimeofday(&ntv,NULL);
	tv=ntv;

	signal(SIGCHLD, SIG_IGN);
	
	for(;;)
	{	FD_ZERO(&rds);
		FD_ZERO(&wrs);
		m=s;
		FD_SET(s,&rds);
		istimeout=0;
		for(c=control;c!=NULL;c=c->next)
		{	MFDSET(m,c->ctrl_fd,&rds);
			MFDSET(m,c->gre_fd,&rds);
			for(p=c->ppp;p!=NULL;p=p->next)
				MFDSET(m,p->fd,&rds);
			if( !istimeout )	tv=c->gre_tv;
			tv=TV_MIN(tv,c->gre_tv);
			istimeout=1;
		}
		gettimeofday(&ntv,NULL);
		if( !istimeout )
		{	select(m+1,&rds,&wrs,NULL,NULL);
			gettimeofday(&ntv,NULL);
		}
		else if( !TV_IS_MIN(tv,ntv) )
		{	TV_SUB(tv,ntv);
			select(m+1,&rds,&wrs,NULL,&tv);
			gettimeofday(&ntv,NULL);
		}
		else
		{	FD_ZERO(&rds);
			FD_ZERO(&wrs);
		}
		if( FD_ISSET(s,&rds) )
		{	salen=sizeof(struct sockaddr_in);
			if( (a=accept(s,(struct sockaddr*)&sa,&salen))>=0 )
			{	if( (c=init_control_struct(&control))==NULL )
				{	close(a);
					LOG("Can't init control struct");
				}
				else
				{	c->ctrl_fd=a;
					memcpy(&(c->addr_remote),&sa,sizeof(struct sockaddr_in));
					getsockname(a,(struct sockaddr*)&sa,&salen);
					memcpy(&(c->addr_local),&sa,sizeof(struct sockaddr_in));
				}
			}
		}
		for(cc=&control;(*cc)!=NULL;)
		{	c=*cc;
			if( TV_IS_MIN(c->gre_tv,ntv) )
			{	gre_timeout(c);
				c->gre_tv=ntv;
				TV_ADD((c->gre_tv),(c->gre_dtv));
			}
			if( c->ctrl_fd>=0 && FD_ISSET(c->ctrl_fd,&rds) )
			{	if( read_control_packet(c)<0 )
				{	finish_control_struct(c);
					continue;
				}
			}
			if( c->gre_fd >= 0 && FD_ISSET(c->gre_fd,&rds) )
			{	if( read_gre_packet(c)<0 )
				{	finish_control_struct(c);
					continue;
				}
			}
			for(pp=&(c->ppp);*pp!=NULL;)
			{	if( (*pp)->fd>=0 && FD_ISSET((*pp)->fd,&rds) )
					if( read_ppp_packet(c,(*pp))<0 )
					{
						void * close_packet = prepare_call_close_packet(* pp, LOST_CARRIER);
						if (close_packet) {
							send_packet(c, close_packet);
							free(close_packet);
						}
						unlink_and_release_ppp(&pp,(*pp)->call_id);
						if (*pp == NULL)
							break;
					}
				if ((*pp)->next == NULL)
					break;
				pp=&((*pp)->next);
			}
			if ((*cc)->next == NULL)
				break;
			cc=&((*cc)->next);
		}
	}
}

int main( int argc, char *argv[] )
{ char *p; int i;
	if( (p=strrchr(argv[0],'/'))!=NULL )
		p++;
	else	p=argv[0];
	while ((i=getopt(argc, argv, "vhc:")) != EOF) switch (i) {
		case '?':	fprintf(stderr, "%s: Unknown option, try -h.\n", p);
				return 1;
		case ':':	fprintf(stderr, "%s: Missing argument, try -h.\n", p);
				return 1;
		case 'v':	puts("Version " VERSION);
				return 0;
		case 'h':	printf("%s: Usage: \n"
					"\t%s -h ... this help text\n"
					"\t%s -v ... current version\n"
					"\t%s [-c <filename>] ... start, configure from that file instead of default\n", p, argv[0], argv[0], argv[0]);
				return 0;
	}
	printf("Configured %d pppd cmdlines\n",conf_ppp(PPPD_CMDLINESFILE));
	openlog(p,LOG_PID,LOG_DAEMON);
	LOG("started");
	return(loop());
}