miscutils/last.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * last implementation for busybox
   4  *
   5  * Copyright (C) 2003-2004 by Erik Andersen <andersen@codepoet.org>
   6  *
   7  * Licensed under the GPL version 2, see the file LICENSE in this tarball.
   8  */
   9
  10 #include "libbb.h"
  11 #include <utmp.h>
  12
  13 #ifndef SHUTDOWN_TIME
  14 #  define SHUTDOWN_TIME 254
  15 #endif
  16
  17 /* Grr... utmp char[] members do not have to be nul-terminated.
  18  * Do what we can while still keeping this reasonably small.
  19  * Note: We are assuming the ut_id[] size is fixed at 4. */
  20
  21 #if defined UT_LINESIZE \
  22         && ((UT_LINESIZE != 32) || (UT_NAMESIZE != 32) || (UT_HOSTSIZE != 256))
  23 #error struct utmp member char[] size(s) have changed!
  24 #elif defined __UT_LINESIZE \
  25         && ((__UT_LINESIZE != 32) || (__UT_NAMESIZE != 64) || (__UT_HOSTSIZE != 256))
  26 #error struct utmp member char[] size(s) have changed!
  27 #endif
  28
  29 #if ENABLE_FEATURE_LAST_FANCY
  30
  31 #include "last_fancy.c"
  32
  33 #else
  34
  35 int last_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  36 int last_main(int argc, char **argv ATTRIBUTE_UNUSED)
  37 {
  38         struct utmp ut;
  39         int n, file = STDIN_FILENO;
  40         time_t t_tmp;
  41
  42         if (argc > 1) {
  43                 bb_show_usage();
  44         }
  45         file = xopen(bb_path_wtmp_file, O_RDONLY);
  46
  47         printf("%-10s %-14s %-18s %-12.12s %s\n",
  48                "USER", "TTY", "HOST", "LOGIN", "TIME");
  49         while ((n = full_read(file, &ut, sizeof(ut))) > 0) {
  50                 if (n != sizeof(ut)) {
  51                         bb_perror_msg_and_die("short read");
  52                 }
  53
  54                 if (ut.ut_line[0] == '~') {
  55                         if (strncmp(ut.ut_user, "shutdown", 8) == 0)
  56                                 ut.ut_type = SHUTDOWN_TIME;
  57                         else if (strncmp(ut.ut_user, "reboot", 6) == 0)
  58                                 ut.ut_type = BOOT_TIME;
  59                         else if (strncmp(ut.ut_user, "runlevel", 8) == 0)
  60                                 ut.ut_type = RUN_LVL;
  61                 } else {
  62                         if (ut.ut_name[0] == '\0' || strcmp(ut.ut_name, "LOGIN") == 0) {
  63                                 /* Don't bother.  This means we can't find how long
  64                                  * someone was logged in for.  Oh well. */
  65                                 continue;
  66                         }
  67                         if (ut.ut_type != DEAD_PROCESS
  68                          && ut.ut_name[0] && ut.ut_line[0]
  69                         ) {
  70                                 ut.ut_type = USER_PROCESS;
  71                         }
  72                         if (strcmp(ut.ut_name, "date") == 0) {
  73                                 if (ut.ut_line[0] == '|') {
  74                                         ut.ut_type = OLD_TIME;
  75                                 }
  76                                 if (ut.ut_line[0] == '{') {
  77                                         ut.ut_type = NEW_TIME;
  78                                 }
  79                         }
  80                 }
  81
  82                 if (ut.ut_type != USER_PROCESS) {
  83                         switch (ut.ut_type) {
  84                                 case OLD_TIME:
  85                                 case NEW_TIME:
  86                                 case RUN_LVL:
  87                                 case SHUTDOWN_TIME:
  88                                         continue;
  89                                 case BOOT_TIME:
  90                                         strcpy(ut.ut_line, "system boot");
  91                                         break;
  92                         }
  93                 }
  94                 t_tmp = (time_t)ut.ut_tv.tv_sec;
  95                 printf("%-10s %-14s %-18s %-12.12s\n",
  96                        ut.ut_user, ut.ut_line, ut.ut_host, ctime(&t_tmp) + 4);
  97         }
  98
  99         fflush_stdout_and_exit(EXIT_SUCCESS);
 100 }
 101
 102 #endif