usr.bin/users/users.c

   1 /*      $NetBSD: users.c,v 1.14 2008/07/13 20:07:48 dholland Exp $      */
   2
   3 /*
   4  * Copyright (c) 1980, 1987, 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. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #ifndef lint
  34 __COPYRIGHT("@(#) Copyright (c) 1980, 1987, 1993\
  35  The Regents of the University of California.  All rights reserved.");
  36 #endif /* not lint */
  37
  38 #ifndef lint
  39 #if 0
  40 static char sccsid[] = "@(#)users.c     8.1 (Berkeley) 6/6/93";
  41 #endif
  42 __RCSID("$NetBSD: users.c,v 1.14 2008/07/13 20:07:48 dholland Exp $");
  43 #endif /* not lint */
  44
  45 #include <sys/types.h>
  46
  47 #include <err.h>
  48 #include <time.h>
  49 #include <stdio.h>
  50 #include <stdlib.h>
  51 #include <string.h>
  52 #include <unistd.h>
  53
  54 #include "utmpentry.h"
  55
  56 int     main __P((int, char **));
  57
  58 int
  59 main(argc, argv)
  60         int argc;
  61         char **argv;
  62 {
  63         int ncnt = 0;
  64         int ch;
  65         struct utmpentry *from, *ehead, *save, **nextp;
  66
  67         while ((ch = getopt(argc, argv, "")) != -1)
  68                 switch(ch) {
  69                 case '?':
  70                 default:
  71                         (void)fprintf(stderr, "usage: %s\n", getprogname());
  72                         exit(1);
  73                 }
  74         argc -= optind;
  75         argv += optind;
  76
  77         ncnt = getutentries(NULL, &ehead);
  78
  79         if (ncnt == 0)
  80                 return 0;
  81
  82         /*
  83          * XXX the utmp list belongs to getutentries and we shouldn't
  84          * sort it in place. Since we don't call endutentries and we
  85          * don't call getutentries again it doesn't matter, but it's
  86          * untidy. Maybe give getutentries a sort function? It has to
  87          * sort anyway if it's merging utmp and utmpx data.
  88          */
  89
  90         from = ehead;
  91         ehead = NULL;
  92         while (from != NULL) {
  93                 for (nextp = &ehead;
  94                     (*nextp) && strcmp(from->name, (*nextp)->name) > 0;
  95                     nextp = &(*nextp)->next)
  96                         continue;
  97                 save = from;
  98                 from = from->next;
  99                 save->next = *nextp;
 100                 *nextp = save;
 101         }
 102
 103         save = ehead;
 104         (void)printf("%s", ehead->name);
 105
 106         for (from = ehead->next; from; from = from->next)
 107                 if (strcmp(save->name, from->name) != 0) {
 108                         (void)printf(" %s", from->name);
 109                         save = from;
 110                 }
 111
 112         (void)printf("\n");
 113         exit(0);
 114 }