text: /*	$NetBSD: ctl_transact.c,v 1.3 1997/10/20 00:37:16 lukem Exp $	*/
  /*
   * Copyright (c) 1983 Regents of the University of California.
   * All rights reserved.  The Berkeley software License Agreement
   * specifies the terms and conditions for redistribution.
   */
  
  #include "bsd.h"
  
  #if	defined(TALK_43) || defined(TALK_42)
  
  #include <sys/cdefs.h>
  #ifndef lint
  #if 0
  static char sccsid[] = "@(#)ctl_transact.c	5.2 (Berkeley) 3/13/86";
  #else
  __RCSID("$NetBSD: ctl_transact.c,v 1.3 1997/10/20 00:37:16 lukem Exp $");
  #endif
  #endif /* not lint */
  
  #include <sys/time.h>
  #include <unistd.h>
  #include "hunt.h"
  #include "talk_ctl.h"
  
  #define CTL_WAIT 2	/* time to wait for a response, in seconds */
  #define MAX_RETRY 5
  
  /*
   * SOCKDGRAM is unreliable, so we must repeat messages if we have
   * not recieved an acknowledgement within a reasonable amount
   * of time
   */
  void
  ctl_transact(target, msg, type, rp)
  	struct in_addr target;
  	CTL_MSG msg;
  	int type;
  	CTL_RESPONSE *rp;
  {
  	fd_set read_mask, ctl_mask;
  	int nready, cc, retries;
  	struct timeval wait;
  
  	nready = 0;
  	msg.type = type;
  	daemon_addr.sin_addr = target;
  	daemon_addr.sin_port = daemon_port;
  	FD_ZERO(&ctl_mask);
  	FD_SET(ctl_sockt, &ctl_mask);
  
  	/*
  	 * Keep sending the message until a response of
  	 * the proper type is obtained.
  	 */
  	do {
  		wait.tv_sec = CTL_WAIT;
  		wait.tv_usec = 0;
  		/* resend message until a response is obtained */
  		for (retries = MAX_RETRY; retries > 0; retries -= 1) {
  			cc = sendto(ctl_sockt, (char *)&msg, sizeof (msg), 0,
  			    (struct sockaddr *)&daemon_addr, sizeof (daemon_addr));
  			if (cc != sizeof (msg)) {
  				if (errno == EINTR)
  					continue;
  				p_error("Error on write to talk daemon");
  			}
  			read_mask = ctl_mask;
  			nready = select(32, &read_mask, 0, 0, &wait);
  			if (nready < 0) {
  				if (errno == EINTR)
  					continue;
  				p_error("Error waiting for daemon response");
  			}
  			if (nready != 0)
  				break;
  		}
  		if (retries <= 0)
  			break;
  		/*
  		 * Keep reading while there are queued messages 
  		 * (this is not necessary, it just saves extra
  		 * request/acknowledgements being sent)
  		 */
  		do {
  			cc = recv(ctl_sockt, (char *)rp, sizeof (*rp), 0);
  			if (cc < 0) {
  				if (errno == EINTR)
  					continue;
  				p_error("Error on read from talk daemon");
  			}
  			read_mask = ctl_mask;
  			/* an immediate poll */
  			timerclear(&wait);
  			nready = select(32, &read_mask, 0, 0, &wait);
  		} while (nready > 0 && (
  #ifdef	TALK_43
  		    rp->vers != TALK_VERSION ||
  #endif
  		    rp->type != type));
  	} while (
  #ifdef	TALK_43
  	    rp->vers != TALK_VERSION ||
  #endif
  	    rp->type != type);
  	rp->id_num = ntohl(rp->id_num);
  #ifdef	TALK_43
  	rp->addr.sa_family = ntohs(rp->addr.sa_family);
  # else
  	rp->addr.sin_family = ntohs(rp->addr.sin_family);
  # endif
  }
  #endif
  