text: /*-
   * SPDX-License-Identifier: BSD-4-Clause
   *
   * Copyright (c) 1996 John M. Vinopal
   * Copyright (c) 2018 Philip Paeps
   * 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 for the NetBSD Project
   *	by John M. Vinopal.
   * 4. The name of the author may not be used to endorse or promote products
   *    derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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
  __RCSID("$FreeBSD$");
  __RCSID("$NetBSD: lastlogin.c,v 1.4 1998/02/03 04:45:35 perry Exp $");
  #endif
  
  #include <err.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <time.h>
  #include <unistd.h>
  #include <utmpx.h>
  
  #include <libxo/xo.h>
  
  	int	main(int, char **);
  static	void	output(struct utmpx *);
  static	void	usage(void);
  static int	utcmp_user(const void *, const void *);
  
  static int	order = 1;
  static const char *file = NULL;
  static int	(*utcmp)(const void *, const void *) = utcmp_user;
  
  static int
  utcmp_user(const void *u1, const void *u2)
  {
  
  	return (order * strcmp(((const struct utmpx *)u1)->ut_user,
  	    ((const struct utmpx *)u2)->ut_user));
  }
  
  static int
  utcmp_time(const void *u1, const void *u2)
  {
  	time_t t1, t2;
  
  	t1 = ((const struct utmpx *)u1)->ut_tv.tv_sec;
  	t2 = ((const struct utmpx *)u2)->ut_tv.tv_sec;
  	return (t1 < t2 ? order : t1 > t2 ? -order : 0);
  }
  
  int
  main(int argc, char *argv[])
  {
  	int	ch, i, ulistsize;
  	struct utmpx *u, *ulist;
  
  	argc = xo_parse_args(argc, argv);
  	if (argc < 0)
  		exit(1);
  
  	while ((ch = getopt(argc, argv, "f:rt")) != -1) {
  		switch (ch) {
  		case 'f':
  			file = optarg;
  			break;
  		case 'r':
  			order = -1;
  			break;
  		case 't':
  			utcmp = utcmp_time;
  			break;
  		default:
  			usage();
  		}
  	}
  	argc -= optind;
  	argv += optind;
  
  	xo_open_container("lastlogin-information");
  	xo_open_list("lastlogin");
  
  	if (argc > 0) {
  		/* Process usernames given on the command line. */
  		for (i = 0; i < argc; i++) {
  			if (setutxdb(UTXDB_LASTLOGIN, file) != 0)
  				xo_err(1, "failed to open lastlog database");
  			if ((u = getutxuser(argv[i])) == NULL) {
  				xo_warnx("user '%s' not found", argv[i]);
  				continue;
  			}
  			output(u);
  			endutxent();
  		}
  	} else {
  		/* Read all lastlog entries, looking for active ones. */
  		if (setutxdb(UTXDB_LASTLOGIN, file) != 0)
  			xo_err(1, "failed to open lastlog database");
  		ulist = NULL;
  		ulistsize = 0;
  		while ((u = getutxent()) != NULL) {
  			if (u->ut_type != USER_PROCESS)
  				continue;
  			if ((ulistsize % 16) == 0) {
  				ulist = realloc(ulist,
  				    (ulistsize + 16) * sizeof(struct utmpx));
  				if (ulist == NULL)
  					xo_err(1, "malloc");
  			}
  			ulist[ulistsize++] = *u;
  		}
  		endutxent();
  
  		qsort(ulist, ulistsize, sizeof(struct utmpx), utcmp);
  		for (i = 0; i < ulistsize; i++)
  			output(&ulist[i]);
  	}
  
  	xo_close_list("lastlogin");
  	xo_close_container("lastlogin-information");
  	xo_finish();
  
  	exit(0);
  }
  
  /* Duplicate the output of last(1) */
  static void
  output(struct utmpx *u)
  {
  	time_t t = u->ut_tv.tv_sec;
  
  	xo_open_instance("lastlogin");
  	xo_emit("{:user/%-10s/%s} {:tty/%-8s/%s} {:from/%-22.22s/%s}",
  		u->ut_user, u->ut_line, u->ut_host);
  	xo_attr("seconds", "%lu", (unsigned long)t);
  	xo_emit(" {:login-time/%.24s/%.24s}\n", ctime(&t));
  	xo_close_instance("lastlogin");
  }
  
  static void
  usage(void)
  {
  	xo_error("usage: lastlogin [-f file] [-rt] [user ...]\n");
  	xo_finish();
  	exit(1);
  }
  