/*-
 * SPDX-License-Identifier: BSD-4-Clause
 *
 * Copyright (c) 1993, John Brezak
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */


#include <sys/types.h>
#include <sys/socket.h>

#include <rpc/rpc.h>
#include <rpc/pmap_clnt.h>
#include <rpcsvc/rnusers.h>

#include <arpa/inet.h>

#include <err.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <timeconv.h>
#include <unistd.h>

#define MAX_INT         0x7fffffff
#define HOST_WIDTH      20
#define LINE_WIDTH      15

static int longopt;
static int allopt;

static struct host_list {
        struct  host_list *next;
        struct  in_addr addr;
} *hosts;

static int
search_host(struct in_addr addr)
{
        struct host_list *hp;

        if (hosts == NULL)
                return (0);

        for (hp = hosts; hp != NULL; hp = hp->next) {
                if (hp->addr.s_addr == addr.s_addr)
                        return (1);
        }
        return (0);
}

static void
remember_host(struct in_addr addr)
{
        struct host_list *hp;

        if ((hp = (struct host_list *)malloc(sizeof(struct host_list))) == NULL)
                errx(1, "no memory");
        hp->addr.s_addr = addr.s_addr;
        hp->next = hosts;
        hosts = hp;
}

static int
rusers_reply(void *replyp, struct sockaddr_in *raddrp)
{
        unsigned int x;
        int idle;
        char date[32], idle_time[64], remote[64];
        struct hostent *hp;
        utmpidlearr *up, u;
        char *host;
        int days, hours, minutes, seconds;

        up = &u;
        memcpy(up, replyp, sizeof(*up));
        if (search_host(raddrp->sin_addr))
                return (0);

        if (!allopt && up->utmpidlearr_len == 0)
                return (0);

        hp = gethostbyaddr((char *)&raddrp->sin_addr.s_addr,
            sizeof(struct in_addr), AF_INET);
        if (hp != NULL)
                host = hp->h_name;
        else
                host = inet_ntoa(raddrp->sin_addr);

        if (!longopt)
                printf("%-*s ", HOST_WIDTH, host);

        for (x = 0; x < up->utmpidlearr_len; x++) {
                time_t t = _int_to_time(up->utmpidlearr_val[x].ui_utmp.ut_time);
                strncpy(date, &(ctime(&t)[4]), sizeof(date) - 1);

                idle = up->utmpidlearr_val[x].ui_idle;
                sprintf(idle_time, "  :%02d", idle);
                if (idle == MAX_INT)
                        strcpy(idle_time, "??");
                else if (idle == 0)
                        strcpy(idle_time, "");
                else {
                        seconds = idle;
                        days = seconds / (60 * 60 * 24);
                        seconds %= (60 * 60 * 24);
                        hours = seconds / (60 * 60);
                        seconds %= (60 * 60);
                        minutes = seconds / 60;
                        seconds %= 60;
                        if (idle > 60)
                                sprintf(idle_time, "%d:%02d", minutes, seconds);
                        if (idle >= (60 * 60))
                                sprintf(idle_time, "%d:%02d:%02d",
                                    hours, minutes, seconds);
                        if (idle >= (24 * 60 * 60))
                                sprintf(idle_time, "%d days, %d:%02d:%02d",
                                    days, hours, minutes, seconds);
                }

                strncpy(remote, up->utmpidlearr_val[x].ui_utmp.ut_host,
                    sizeof(remote) - 1);
                if (strlen(remote) != 0)
                        sprintf(remote, "(%.16s)",
                            up->utmpidlearr_val[x].ui_utmp.ut_host);

                if (longopt)
                        printf("%-8.8s %*s:%-*.*s %-12.12s  %6s %.18s\n",
                            up->utmpidlearr_val[x].ui_utmp.ut_name,
                            HOST_WIDTH, host, LINE_WIDTH, LINE_WIDTH,
                            up->utmpidlearr_val[x].ui_utmp.ut_line, date,
                            idle_time, remote );
                else
                        printf("%s ",
                            up->utmpidlearr_val[x].ui_utmp.ut_name);
        }
        if (!longopt)
                putchar('\n');

        remember_host(raddrp->sin_addr);
        return (0);
}

static void
onehost(char *host)
{
        utmpidlearr up;
        CLIENT *rusers_clnt;
        struct sockaddr_in addr;
        struct hostent *hp;
        struct timeval tv;

        hp = gethostbyname(host);
        if (hp == NULL)
                errx(1, "unknown host \"%s\"", host);

        rusers_clnt = clnt_create(host, RUSERSPROG, RUSERSVERS_IDLE, "udp");
        if (rusers_clnt == NULL)
                errx(1, "%s", clnt_spcreateerror(""));

        memset(&up, 0, sizeof(up));
        tv.tv_sec = 15; /* XXX ?? */
        tv.tv_usec = 0;
        if (clnt_call(rusers_clnt, RUSERSPROC_NAMES, (xdrproc_t)xdr_void, NULL,
            (xdrproc_t)xdr_utmpidlearr, &up, tv) != RPC_SUCCESS)
                errx(1, "%s", clnt_sperror(rusers_clnt, ""));
        memcpy(&addr.sin_addr.s_addr, hp->h_addr, sizeof(addr.sin_addr.s_addr));
        rusers_reply(&up, &addr);
        clnt_destroy(rusers_clnt);
}

static void
allhosts(void)
{
        utmpidlearr up;
        enum clnt_stat clnt_stat;

        memset(&up, 0, sizeof(up));
        clnt_stat = clnt_broadcast(RUSERSPROG, RUSERSVERS_IDLE,
            RUSERSPROC_NAMES, (xdrproc_t)xdr_void, NULL,
            (xdrproc_t)xdr_utmpidlearr, (char *)&up,
            (clnt_broadcast_resultproc_t)rusers_reply);
        if (clnt_stat != RPC_SUCCESS && clnt_stat != RPC_TIMEDOUT)
                errx(1, "%s", clnt_sperrno(clnt_stat));
}

static void
usage(void)
{

        fprintf(stderr, "usage: rusers [-al] [host ...]\n");
        exit(1);
}

int
main(int argc, char *argv[])
{
        int ch;

        while ((ch = getopt(argc, argv, "al")) != -1)
                switch (ch) {
                case 'a':
                        allopt++;
                        break;
                case 'l':
                        longopt++;
                        break;
                default:
                        usage();
                        /* NOTREACHED */
                }

        setlinebuf(stdout);
        if (argc == optind)
                allhosts();
        else {
                for (; optind < argc; optind++)
                        (void)onehost(argv[optind]);
        }
        exit(0);
}