usr.bin/talk/get_names.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*  Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/*    All Rights Reserved   */

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include "talk.h"
#include "ctl.h"
#include <locale.h>
#include <pwd.h>
#include <sys/systeminfo.h>

char *getlogin(), *ttyname(int);

extern CTL_MSG msg;

/*
 * Determine the local and remote user, tty, and machines
 */

struct hostent *gethostbyname();

void
get_names(argc, argv)
int argc;
char *argv[];
{
    char hostname[HOST_NAME_LENGTH + 1];
    char *rem_name;
    char *my_name;
    char *my_machine_name;
    char *rem_machine_name;
    char *my_tty;
    char *rem_tty;
    char *ptr;
    int name_length;

    if (argc < 2) {
        fprintf(stderr,
            "Usage: talk %s\n", gettext("address [terminal]"));
        exit(1);
    }
    if (!isatty(0)) {
        fprintf(stderr,
    gettext("Standard input must be a tty, not a pipe or a file\n"));
        exit(1);
    }

    if (!isatty(1)) {
        fprintf(stderr,
    gettext("Standard output must be a tty, not a pipe or a file\n"));
        exit(1);
    }

    if ((my_name = getlogin()) == NULL) {
    struct passwd *pass = getpwuid(getuid());
    if (pass != NULL)
        my_name = pass->pw_name;
    }
    if (my_name == NULL) {
        fprintf(stderr,
    gettext("Who are you?  You have no entry in /etc/utmp!  Aborting..\n"));
        exit(1);
    }

    name_length = HOST_NAME_LENGTH;
    (void) sysinfo(SI_HOSTNAME, hostname, name_length);
    my_machine_name = hostname;

    my_tty = strrchr(ttyname(0), '/') + 1;

    /*
     * check for, and strip out, the machine name of the target
     */

    for (ptr = argv[1]; *ptr != '\0' &&
             *ptr != '@' &&
             *ptr != ':' &&
             *ptr != '!' &&
             *ptr != '.'; ptr++) {
    }

    if (*ptr == '\0') {

        /* this is a local to local talk */

    rem_name = argv[1];
    rem_machine_name = my_machine_name;

    } else {

    if (*ptr == '@') {
        /* user@host */
        rem_name = argv[1];
        rem_machine_name = ptr + 1;
    } else {
        /* host.user or host!user or host:user */
        rem_name = ptr + 1;
        rem_machine_name = argv[1];
    }
    *ptr = '\0';
    }


    if (argc > 2) {
    rem_tty = argv[2];  /* tty name is arg 2 */
    } else {
    rem_tty = "";
    }

    get_addrs(my_machine_name, rem_machine_name);

    /* Load these useful values into the standard message header */

    msg.id_num = 0;

    strncpy(msg.l_name, my_name, NAME_SIZE);
    msg.l_name[NAME_SIZE - 1] = '\0';

    strncpy(msg.r_name, rem_name, NAME_SIZE);
    msg.r_name[NAME_SIZE - 1] = '\0';

    strncpy(msg.r_tty, rem_tty, TTY_SIZE);
    msg.r_tty[TTY_SIZE - 1] = '\0';
}