1 /* $NetBSD: get_names.c,v 1.7 1998/07/26 22:26:29 mycroft 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 #if 0 39 static char sccsid[] = "@(#)get_names.c 8.1 (Berkeley) 6/6/93"; 40 #endif 41 __RCSID("$NetBSD: get_names.c,v 1.7 1998/07/26 22:26:29 mycroft Exp $"); 42 #endif /* not lint */ 43 44 #include "talk.h" 45 #include <sys/param.h> 46 #include <pwd.h> 47 #include <unistd.h> 48 49 extern CTL_MSG msg; 50 51 /* 52 * Determine the local and remote user, tty, and machines 53 */ 54 void 55 get_names(argc, argv) 56 int argc; 57 char *argv[]; 58 { 59 char hostname[MAXHOSTNAMELEN + 1]; 60 const char *his_name, *my_name; 61 const char *my_machine_name, *his_machine_name; 62 char *his_tty; 63 char *cp; 64 char *names; 65 66 if (argc < 2 ) { 67 printf("Usage: talk user [ttyname]\n"); 68 exit(-1); 69 } 70 if (!isatty(0)) { 71 printf("Standard input must be a tty, not a pipe or a file\n"); 72 exit(-1); 73 } 74 if ((my_name = getlogin()) == NULL) { 75 struct passwd *pw; 76 77 if ((pw = getpwuid(getuid())) == NULL) { 78 printf("You don't exist. Go away.\n"); 79 exit(-1); 80 } 81 my_name = pw->pw_name; 82 } 83 gethostname(hostname, sizeof (hostname)); 84 hostname[sizeof(hostname) - 1] = '\0'; 85 my_machine_name = hostname; 86 /* check for, and strip out, the machine name of the target */ 87 names = strdup(argv[1]); 88 for (cp = names; *cp && !strchr("@:!.", *cp); cp++) 89 ; 90 if (*cp == '\0') { 91 /* this is a local to local talk */ 92 his_name = names; 93 his_machine_name = my_machine_name; 94 } else { 95 if (*cp++ == '@') { 96 /* user@host */ 97 his_name = names; 98 his_machine_name = cp; 99 } else { 100 /* host.user or host!user or host:user */ 101 his_name = cp; 102 his_machine_name = names; 103 } 104 *--cp = '\0'; 105 } 106 if (argc > 2) 107 his_tty = argv[2]; /* tty name is arg 2 */ 108 else 109 his_tty = ""; 110 get_addrs(my_machine_name, his_machine_name); 111 /* 112 * Initialize the message template. 113 */ 114 msg.vers = TALK_VERSION; 115 msg.addr.sa_family = htons(AF_INET); 116 msg.ctl_addr.sa_family = htons(AF_INET); 117 msg.id_num = htonl(0); 118 strncpy(msg.l_name, my_name, NAME_SIZE); 119 msg.l_name[NAME_SIZE - 1] = '\0'; 120 strncpy(msg.r_name, his_name, NAME_SIZE); 121 msg.r_name[NAME_SIZE - 1] = '\0'; 122 strncpy(msg.r_tty, his_tty, TTY_SIZE); 123 msg.r_tty[TTY_SIZE - 1] = '\0'; 124 } 125