/*      $NetBSD: rwho.c,v 1.19 2009/04/13 07:11:37 lukem Exp $  */

/*
 * Copyright (c) 1983, 1993
 *      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.
 */

#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1983, 1993\
 The Regents of the University of California.  All rights reserved.");
#endif /* not lint */

#ifndef lint
/*static char sccsid[] = "from: @(#)rwho.c      8.1 (Berkeley) 6/6/93";*/
__RCSID("$NetBSD: rwho.c,v 1.19 2009/04/13 07:11:37 lukem Exp $");
#endif /* not lint */

#include <sys/param.h>
#include <sys/file.h>

#include <protocols/rwhod.h>

#include <dirent.h>
#include <err.h>
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <fcntl.h>
#include <unistd.h>
#include <utmp.h>
#include <sysexits.h>

static void usage(void) __dead;
static int utmpcmp(const void *, const void *);

/* 
 * this macro should be shared with ruptime.
 */
#define DOWN(w,now)     ((now) - (w).wd_recvtime > 11 * 60)
#define WHDRSIZE        (sizeof(struct whod) - \
    sizeof (((struct whod *)NULL)->wd_we))

struct  my_utmp {
        char    myhost[MAXHOSTNAMELEN];
        int     myidle;
        struct  outmp myutmp;
};

int
main(int argc, char **argv)
{
        DIR *dirp;
        struct dirent *dp;
        struct whoent *we;
        struct whod wd;
        struct my_utmp *mp, *start;
        time_t now;
        int ch;
        size_t width, n, i, nhosts, nusers, namount;
        int aflg, qflg, hflg;

        setprogname(argv[0]);
        (void)setlocale(LC_TIME, "");
        aflg = nusers = nhosts = qflg = hflg = 0;
        namount = 40;
        start = NULL;
        now = 0;

        while ((ch = getopt(argc, argv, "aHq")) != -1)
                switch(ch) {
                case 'a':
                        aflg = 1;
                        break;
                case 'q':
                        qflg = 1;
                        break;
                case 'H':
                        hflg = 1;
                        break;
                default:
                        usage();
                }

        if(optind != argc)
                usage();

        if (qflg) {
                aflg = 0;
                hflg = 0;
        }

        if (chdir(_PATH_RWHODIR) || (dirp = opendir(".")) == NULL)
                err(EXIT_FAILURE, "Cannot access `%s'", _PATH_RWHODIR);

        (void)time(&now);

        if ((start = malloc(sizeof(*start) * namount)) == NULL)
                err(EXIT_FAILURE, "malloc");

        while ((dp = readdir(dirp)) != NULL) {
                int f;
                ssize_t cc;

                if (dp->d_ino == 0 || strncmp(dp->d_name, "whod.", 5))
                        continue;

                f = open(dp->d_name, O_RDONLY);
                if (f < 0)
                        continue;
                cc = read(f, &wd, sizeof (wd));
                if (cc < (ssize_t)WHDRSIZE) {
                        (void)close(f);
                        continue;
                }
                nhosts++;
                if (DOWN(wd, now)) {
                        (void)close(f);
                        continue;
                }
                cc -= WHDRSIZE;
                we = wd.wd_we;
                for (n = cc / sizeof (struct whoent); n > 0; n--) {
                        if (aflg == 0 && we->we_idle >= 60*60) {
                                we++;
                                continue;
                        }

                        if (nusers == namount) {
                                namount = namount + 40;
                                if ((start = realloc(start,
                                    sizeof(struct my_utmp) * namount)) == NULL)
                                        err(1, "realloc");
                        }

                        mp = start + nusers;
        
                        mp->myutmp = we->we_utmp;
                        mp->myidle = we->we_idle;
                        (void)strcpy(mp->myhost, wd.wd_hostname);
                        nusers++; we++; mp++;
                }
                (void)close(f);
        }

        if (nhosts == 0)
                errx(EX_OK, "No hosts in `%s'.", _PATH_RWHODIR);

        mp = start;
        qsort(start, nusers, sizeof(*start), utmpcmp);
        width = 0;
        for (i = 0; i < nusers; i++) {
                size_t j = strlen(mp->myhost) + 1 + strlen(mp->myutmp.out_line);
                if (j > width)
                        width = j;
                mp++;
        }
        mp = start;
        if (hflg) {
                (void)printf("%-*.*s %-*s %-12s %-*s\n", UT_NAMESIZE,
                    UT_NAMESIZE, "USER", (int)width, "LINE", "WHEN",
                    (int)width, "IDLE");
        }
        for (i = 0; i < nusers; i++) {
                char buf[BUFSIZ], cbuf[80];
                time_t t;

                if (qflg) {
                        (void)printf("%-*.*s\n", UT_NAMESIZE, UT_NAMESIZE,
                            mp->myutmp.out_name);
                        mp++;
                        continue;
                }
                t = mp->myutmp.out_time;
                (void)strftime(cbuf, sizeof(cbuf), "%c", localtime(&t));
                (void)snprintf(buf, sizeof(buf), "%s:%s", mp->myhost,
                    mp->myutmp.out_line);
                (void)printf("%-*.*s %-*s %.12s", UT_NAMESIZE, UT_NAMESIZE,
                    mp->myutmp.out_name, (int)width, buf, cbuf + 4);
                mp->myidle /= 60;
                if (mp->myidle) {
                        if (aflg) {
                                if (mp->myidle >= 100 * 60)
                                        mp->myidle = 100 * 60 - 1;
                                if (mp->myidle >= 60)
                                        (void)printf(" %2d", mp->myidle / 60);
                                else
                                        (void)printf("   ");
                        } else
                                (void)printf(" ");
                        (void)printf(":%02d", mp->myidle % 60);
                }
                (void)printf("\n");
                mp++;
        }

        if (qflg)
                (void)printf("# users = %zd\n", nusers);

        return EX_OK;
}

static int
utmpcmp(const void *v1, const void *v2)
{
        const struct my_utmp *u1, *u2;
        int rc;

        u1 = v1;
        u2 = v2;
        rc = strncmp(u1->myutmp.out_name, u2->myutmp.out_name, 8);
        if (rc)
                return rc;
        rc = strcmp(u1->myhost, u2->myhost);
        if (rc)
                return rc;
        return strncmp(u1->myutmp.out_line, u2->myutmp.out_line, 8);
}

static void
usage(void)
{
        (void)fprintf(stderr, "Usage: %s [-aHq]\n", getprogname());
        exit(1);
}