/*
 * Copyright (c) 1983, 1993, 1994
 *      The Regents of the University of California.  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. 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.
 *
 * @(#) Copyright (c) 1983, 1993, 1994 The Regents of the University of California.  All rights reserved.
 * @(#)ruptime.c        8.2 (Berkeley) 4/5/94
 * $FreeBSD: src/usr.bin/ruptime/ruptime.c,v 1.12.2.1 2000/06/30 09:45:00 ps Exp $
 */

#include <sys/param.h>

#include <protocols/rwhod.h>

#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

static struct hs {
        struct  whod *hs_wd;
        int     hs_nusers;
} *hs;

#define LEFTEARTH(h)    (now - (h) > 4*24*60*60)
#define ISDOWN(h)       (now - (h)->hs_wd->wd_recvtime > 11 * 60)
#define WHDRSIZE        (sizeof(struct whod) - \
                            sizeof(((struct whod *)NULL)->wd_we))

static size_t nhosts;
static time_t now;
static int rflg = 1;

static int       hscmp(const void *, const void *);
static char     *interval(time_t, const char *);
static int       lcmp(const void *, const void *);
static int       tcmp(const void *, const void *);
static int       ucmp(const void *, const void *);
static void      usage(void) __dead2;

int
main(int argc, char *argv[])
{
        struct dirent *dp;
        struct hs *hsp = NULL;
        struct whod *wd;
        struct whoent *we;
        DIR *dirp;
        size_t hspace;
        int aflg, ch, fd, maxloadav;
        char buf[sizeof(struct whod)];
        int (*cmp)(const void *, const void *);
        u_int cc, i;

        aflg = 0;
        cmp = hscmp;
        while ((ch = getopt(argc, argv, "alrut")) != -1)
                switch (ch) {
                case 'a':
                        aflg = 1;
                        break;
                case 'l':
                        cmp = lcmp;
                        break;
                case 'r':
                        rflg = -1;
                        break;
                case 't':
                        cmp = tcmp;
                        break;
                case 'u':
                        cmp = ucmp;
                        break;
                default:
                        usage();
                }
        argc -= optind;
        argv += optind;

        if (argc != 0)
                usage();

        if (chdir(_PATH_RWHODIR) || (dirp = opendir(".")) == NULL)
                err(1, "%s", _PATH_RWHODIR);

        maxloadav = -1;
        for (nhosts = hspace = 0; (dp = readdir(dirp)) != NULL;) {
                if (dp->d_ino == 0 || strncmp(dp->d_name, "whod.", 5))
                        continue;
                if ((fd = open(dp->d_name, O_RDONLY, 0)) < 0) {
                        warn("%s", dp->d_name);
                        continue;
                }
                cc = read(fd, buf, sizeof(struct whod));
                (void)close(fd);

                if (cc < WHDRSIZE)
                        continue;
                if (LEFTEARTH(((struct whod *)buf)->wd_recvtime))
                        continue;
                if (nhosts == hspace) {
                        hspace += 40;
                        if ((hs = realloc(hs, hspace * sizeof(*hs))) == NULL)
                                err(1, NULL);
                        hsp = hs + nhosts;
                }

                if ((hsp->hs_wd = malloc((size_t)WHDRSIZE)) == NULL)
                        err(1, NULL);
                memmove(hsp->hs_wd, buf, (size_t)WHDRSIZE);

                for (wd = (struct whod *)buf, i = 0; i < 2; ++i)
                        if (wd->wd_loadav[i] > maxloadav)
                                maxloadav = wd->wd_loadav[i];

                for (hsp->hs_nusers = 0,
                    we = (struct whoent *)(buf + cc); --we >= wd->wd_we;)
                        if (aflg || we->we_idle < 3600)
                                ++hsp->hs_nusers;
                ++hsp;
                ++nhosts;
        }
        if (nhosts == 0)
                errx(1, "no hosts in %s", _PATH_RWHODIR);

        (void)time(&now);
        qsort(hs, nhosts, sizeof(hs[0]), cmp);
        for (i = 0; i < nhosts; i++) {
                hsp = &hs[i];
                if (ISDOWN(hsp)) {
                        (void)printf("%-12.12s%s\n", hsp->hs_wd->wd_hostname,
                            interval(now - hsp->hs_wd->wd_recvtime, "down"));
                        continue;
                }
                (void)printf(
                    "%-12.12s%s,  %4d user%s  load %*.2f, %*.2f, %*.2f\n",
                    hsp->hs_wd->wd_hostname,
                    interval((time_t)hsp->hs_wd->wd_sendtime -
                        (time_t)hsp->hs_wd->wd_boottime, "  up"),
                    hsp->hs_nusers,
                    hsp->hs_nusers == 1 ? ", " : "s,",
                    maxloadav >= 1000 ? 5 : 4,
                        hsp->hs_wd->wd_loadav[0] / 100.0,
                    maxloadav >= 1000 ? 5 : 4,
                        hsp->hs_wd->wd_loadav[1] / 100.0,
                    maxloadav >= 1000 ? 5 : 4,
                        hsp->hs_wd->wd_loadav[2] / 100.0);
        }
        exit(0);
}

static char *
interval(time_t tval, const char *updown)
{
        static char resbuf[32];
        int days, hours, minutes;

        if (tval < 0) {
                (void)snprintf(resbuf, sizeof(resbuf), "   %s ??:??", updown);
                return (resbuf);
        }
        /* round to minutes. */
        minutes = howmany(tval, 60);
        hours = minutes / 60;
        minutes %= 60;
        days = hours / 24;
        hours %= 24;
        if (days)
                (void)snprintf(resbuf, sizeof(resbuf),
                    "%s %3d+%02d:%02d", updown, days, hours, minutes);
        else
                (void)snprintf(resbuf, sizeof(resbuf),
                    "%s     %2d:%02d", updown, hours, minutes);
        return (resbuf);
}

#define HS(a)   ((const struct hs *)(a))

/* Alphabetical comparison. */
static int
hscmp(const void *a1, const void *a2)
{
        return (rflg *
            strcmp(HS(a1)->hs_wd->wd_hostname, HS(a2)->hs_wd->wd_hostname));
}

/* Load average comparison. */
static int
lcmp(const void *a1, const void *a2)
{
        if (ISDOWN(HS(a1)))
                if (ISDOWN(HS(a2)))
                        return (tcmp(a1, a2));
                else
                        return (rflg);
        else if (ISDOWN(HS(a2)))
                return (-rflg);
        else
                return (rflg *
                   (HS(a2)->hs_wd->wd_loadav[0] - HS(a1)->hs_wd->wd_loadav[0]));
}

/* Number of users comparison. */
static int
ucmp(const void *a1, const void *a2)
{
        if (ISDOWN(HS(a1)))
                if (ISDOWN(HS(a2)))
                        return (tcmp(a1, a2));
                else
                        return (rflg);
        else if (ISDOWN(HS(a2)))
                return (-rflg);
        else
                return (rflg * (HS(a2)->hs_nusers - HS(a1)->hs_nusers));
}

/* Uptime comparison. */
static int
tcmp(const void *a1, const void *a2)
{
        return (rflg * (
                (ISDOWN(HS(a2)) ? HS(a2)->hs_wd->wd_recvtime - now
                    : HS(a2)->hs_wd->wd_sendtime - HS(a2)->hs_wd->wd_boottime)
                -
                (ISDOWN(HS(a1)) ? HS(a1)->hs_wd->wd_recvtime - now
                    : HS(a1)->hs_wd->wd_sendtime - HS(a1)->hs_wd->wd_boottime)
        ));
}

static void
usage(void)
{
        (void)fprintf(stderr, "usage: ruptime [-alrut]\n");
        exit(1);
}