usr/src/cmd/cmd-inet/usr.bin/talk/get_names.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T     */
  28 /*        All Rights Reserved   */
  29
  30 /*
  31  * University Copyright- Copyright (c) 1982, 1986, 1988
  32  * The Regents of the University of California
  33  * All Rights Reserved
  34  *
  35  * University Acknowledgment- Portions of this document are derived from
  36  * software developed by the University of California, Berkeley, and its
  37  * contributors.
  38  */
  39
  40 #pragma ident   "%Z%%M% %I%     %E% SMI"
  41
  42 #include "talk.h"
  43 #include "ctl.h"
  44 #include <locale.h>
  45 #include <pwd.h>
  46 #include <sys/systeminfo.h>
  47
  48 char *getlogin(), *ttyname(int);
  49
  50 extern CTL_MSG msg;
  51
  52 /*
  53  * Determine the local and remote user, tty, and machines
  54  */
  55
  56 struct hostent *gethostbyname();
  57
  58 void
  59 get_names(argc, argv)
  60 int argc;
  61 char *argv[];
  62 {
  63         char hostname[HOST_NAME_LENGTH + 1];
  64         char *rem_name;
  65         char *my_name;
  66         char *my_machine_name;
  67         char *rem_machine_name;
  68         char *my_tty;
  69         char *rem_tty;
  70         char *ptr;
  71         int name_length;
  72
  73         if (argc < 2) {
  74                 fprintf(stderr,
  75                     "Usage: talk %s\n", gettext("address [terminal]"));
  76                 exit(1);
  77         }
  78         if (!isatty(0)) {
  79                 fprintf(stderr,
  80         gettext("Standard input must be a tty, not a pipe or a file\n"));
  81                 exit(1);
  82         }
  83
  84         if (!isatty(1)) {
  85                 fprintf(stderr,
  86         gettext("Standard output must be a tty, not a pipe or a file\n"));
  87                 exit(1);
  88         }
  89
  90         if ((my_name = getlogin()) == NULL) {
  91         struct passwd *pass = getpwuid(getuid());
  92         if (pass != NULL)
  93                 my_name = pass->pw_name;
  94         }
  95         if (my_name == NULL) {
  96                 fprintf(stderr,
  97         gettext("Who are you?  You have no entry in /etc/utmp!  Aborting..\n"));
  98                 exit(1);
  99         }
 100
 101         name_length = HOST_NAME_LENGTH;
 102         (void) sysinfo(SI_HOSTNAME, hostname, name_length);
 103         my_machine_name = hostname;
 104
 105         my_tty = strrchr(ttyname(0), '/') + 1;
 106
 107         /*
 108          * check for, and strip out, the machine name of the target
 109          */
 110
 111         for (ptr = argv[1]; *ptr != '\0' &&
 112                          *ptr != '@' &&
 113                          *ptr != ':' &&
 114                          *ptr != '!' &&
 115                          *ptr != '.'; ptr++) {
 116         }
 117
 118         if (*ptr == '\0') {
 119
 120                 /* this is a local to local talk */
 121
 122         rem_name = argv[1];
 123         rem_machine_name = my_machine_name;
 124
 125         } else {
 126
 127         if (*ptr == '@') {
 128                 /* user@host */
 129                 rem_name = argv[1];
 130                 rem_machine_name = ptr + 1;
 131         } else {
 132                 /* host.user or host!user or host:user */
 133                 rem_name = ptr + 1;
 134                 rem_machine_name = argv[1];
 135         }
 136         *ptr = '\0';
 137         }
 138
 139
 140         if (argc > 2) {
 141         rem_tty = argv[2];      /* tty name is arg 2 */
 142         } else {
 143         rem_tty = "";
 144         }
 145
 146         get_addrs(my_machine_name, rem_machine_name);
 147
 148         /* Load these useful values into the standard message header */
 149
 150         msg.id_num = 0;
 151
 152         strncpy(msg.l_name, my_name, NAME_SIZE);
 153         msg.l_name[NAME_SIZE - 1] = '\0';
 154
 155         strncpy(msg.r_name, rem_name, NAME_SIZE);
 156         msg.r_name[NAME_SIZE - 1] = '\0';
 157
 158         strncpy(msg.r_tty, rem_tty, TTY_SIZE);
 159         msg.r_tty[TTY_SIZE - 1] = '\0';
 160 }