usr.bin/talk/get_addrs.c

   1 /*      $NetBSD: get_addrs.c,v 1.7 2001/04/06 11:13:46 wiz Exp $        */
   2
   3 /*
   4  * Copyright (c) 1983, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #ifndef lint
  34 #if 0
  35 static char sccsid[] = "@(#)get_addrs.c 8.1 (Berkeley) 6/6/93";
  36 #endif
  37 __RCSID("$NetBSD: get_addrs.c,v 1.7 2001/04/06 11:13:46 wiz Exp $");
  38 #endif /* not lint */
  39
  40 #include "talk.h"
  41 #include <netdb.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <unistd.h>
  45 #include "talk_ctl.h"
  46
  47 void
  48 get_addrs(my_machine_name, his_machine_name)
  49         const char *my_machine_name, *his_machine_name;
  50 {
  51         struct hostent *hp;
  52         struct servent *sp;
  53
  54         msg.pid = htonl(getpid());
  55         /* look up the address of the local host */
  56         hp = gethostbyname(my_machine_name);
  57         if (hp == NULL) {
  58                 fprintf(stderr, "talk: %s: ", my_machine_name);
  59                 herror((char *)NULL);
  60                 exit(1);
  61         }
  62         memmove((char *)&my_machine_addr, hp->h_addr, hp->h_length);
  63         /*
  64          * If the callee is on-machine, just copy the
  65          * network address, otherwise do a lookup...
  66          */
  67         if (strcmp(his_machine_name, my_machine_name)) {
  68                 hp = gethostbyname(his_machine_name);
  69                 if (hp == NULL) {
  70                         fprintf(stderr, "talk: %s: ", his_machine_name);
  71                         herror((char *)NULL);
  72                         exit(1);
  73                 }
  74                 memmove((char *) &his_machine_addr, hp->h_addr, hp->h_length);
  75         } else
  76                 his_machine_addr = my_machine_addr;
  77         /* find the server's port */
  78         sp = getservbyname("ntalk", "udp");
  79         if (sp == 0) {
  80                 fprintf(stderr, "talk: %s/%s: service is not registered.\n",
  81                      "ntalk", "udp");
  82                 exit(1);
  83         }
  84         daemon_port = sp->s_port;
  85 }