get_names.c revision 1.6
1/* $OpenBSD: get_names.c,v 1.6 1998/08/18 04:02:13 millert Exp $ */ 2/* $NetBSD: get_names.c,v 1.4 1994/12/09 02:14:16 jtc Exp $ */ 3 4/* 5 * Copyright (c) 1983, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37#ifndef lint 38#if 0 39static char sccsid[] = "@(#)get_names.c 8.1 (Berkeley) 6/6/93"; 40#endif 41static char rcsid[] = "$OpenBSD: get_names.c,v 1.6 1998/08/18 04:02:13 millert Exp $"; 42#endif /* not lint */ 43 44#include "talk.h" 45#include <sys/param.h> 46#include <pwd.h> 47#include <unistd.h> 48 49extern CTL_MSG msg; 50 51/* 52 * Determine the local and remote user, tty, and machines 53 */ 54void 55get_names(argc, argv) 56 int argc; 57 char *argv[]; 58{ 59 char hostname[MAXHOSTNAMELEN]; 60 char *his_name, *my_name; 61 char *my_machine_name, *his_machine_name; 62 char *his_tty; 63 register char *cp; 64 char *names; 65 66 if ((argc < 2 ) || ('@' == argv[1][0])) { 67 fprintf(stderr, "usage: talk user [ttyname]\n" 68 " talk user@hostname [ttyname]\n"); 69 exit(-1); 70 } 71 if (!isatty(0)) 72 errx(1, "standard input must be a tty, not a pipe or a file"); 73 74 if ((my_name = getlogin()) == NULL) { 75 struct passwd *pw; 76 77 if ((pw = getpwuid(getuid())) == NULL) 78 errx(1, "you don't exist in the passwd file."); 79 my_name = pw->pw_name; 80 } 81 gethostname(hostname, sizeof (hostname)); 82 my_machine_name = hostname; 83 /* check for, and strip out, the machine name of the target */ 84 names = strdup(argv[1]); 85 for (cp = names; *cp && !strchr("@:!.", *cp); cp++) 86 ; 87 if (*cp == '\0') { 88 /* this is a local to local talk */ 89 his_name = names; 90 his_machine_name = my_machine_name; 91 } else { 92 if (*cp++ == '@') { 93 /* user@host */ 94 his_name = names; 95 his_machine_name = cp; 96 } else { 97 /* host.user or host!user or host:user */ 98 his_name = cp; 99 his_machine_name = names; 100 } 101 *--cp = '\0'; 102 } 103 if (argc > 2) 104 his_tty = argv[2]; /* tty name is arg 2 */ 105 else 106 his_tty = ""; 107 get_addrs(my_machine_name, his_machine_name); 108 /* 109 * Initialize the message template. 110 */ 111 msg.vers = TALK_VERSION; 112 msg.addr.sa_family = htons(AF_INET); 113 msg.ctl_addr.sa_family = htons(AF_INET); 114 msg.id_num = htonl(0); 115 strncpy(msg.l_name, my_name, NAME_SIZE); 116 msg.l_name[NAME_SIZE - 1] = '\0'; 117 strncpy(msg.r_name, his_name, NAME_SIZE); 118 msg.r_name[NAME_SIZE - 1] = '\0'; 119 strncpy(msg.r_tty, his_tty, TTY_SIZE); 120 msg.r_tty[TTY_SIZE - 1] = '\0'; 121} 122