miscutils/last_fancy.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * (sysvinit like) last implementation
   4  *
   5  * Copyright (C) 2008 by Patricia Muscalu <patricia.muscalu@axis.com>
   6  *
   7  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8  */
   9
  10 #include "libbb.h"
  11
  12 /* NB: ut_name and ut_user are the same field, use only one name (ut_user)
  13  * to reduce confusion */
  14
  15 #ifndef SHUTDOWN_TIME
  16 #  define SHUTDOWN_TIME 254
  17 #endif
  18
  19 #define HEADER_FORMAT     "%-8.8s %-12.12s %-*.*s %-16.16s %-7.7s %s\n"
  20 #define HEADER_LINE       "USER", "TTY", \
  21         INET_ADDRSTRLEN, INET_ADDRSTRLEN, "HOST", "LOGIN", "  TIME", ""
  22 #define HEADER_LINE_WIDE  "USER", "TTY", \
  23         INET6_ADDRSTRLEN, INET6_ADDRSTRLEN, "HOST", "LOGIN", "  TIME", ""
  24
  25 enum {
  26         NORMAL,
  27         LOGGED,
  28         DOWN,
  29         REBOOT,
  30         CRASH,
  31         GONE
  32 };
  33
  34 enum {
  35         LAST_OPT_W = (1 << 0),  /* -W wide            */
  36         LAST_OPT_f = (1 << 1),  /* -f input file      */
  37         LAST_OPT_H = (1 << 2),  /* -H header          */
  38 };
  39
  40 #define show_wide (option_mask32 & LAST_OPT_W)
  41
  42 static void show_entry(struct utmp *ut, int state, time_t dur_secs)
  43 {
  44         unsigned days, hours, mins;
  45         char duration[32];
  46         char login_time[17];
  47         char logout_time[8];
  48         const char *logout_str;
  49         const char *duration_str;
  50         time_t tmp;
  51
  52         /* manpages say ut_tv.tv_sec *is* time_t,
  53          * but some systems have it wrong */
  54         tmp = ut->ut_tv.tv_sec;
  55         safe_strncpy(login_time, ctime(&tmp), 17);
  56         snprintf(logout_time, 8, "- %s", ctime(&dur_secs) + 11);
  57
  58         dur_secs = MAX(dur_secs - (time_t)ut->ut_tv.tv_sec, (time_t)0);
  59         /* unsigned int is easier to divide than time_t (which may be signed long) */
  60         mins = dur_secs / 60;
  61         days = mins / (24*60);
  62         mins = mins % (24*60);
  63         hours = mins / 60;
  64         mins = mins % 60;
  65
  66 //      if (days) {
  67                 sprintf(duration, "(%u+%02u:%02u)", days, hours, mins);
  68 //      } else {
  69 //              sprintf(duration, " (%02u:%02u)", hours, mins);
  70 //      }
  71
  72         logout_str = logout_time;
  73         duration_str = duration;
  74         switch (state) {
  75         case NORMAL:
  76                 break;
  77         case LOGGED:
  78                 logout_str = "  still";
  79                 duration_str = "logged in";
  80                 break;
  81         case DOWN:
  82                 logout_str = "- down ";
  83                 break;
  84         case REBOOT:
  85                 break;
  86         case CRASH:
  87                 logout_str = "- crash";
  88                 break;
  89         case GONE:
  90                 logout_str = "   gone";
  91                 duration_str = "- no logout";
  92                 break;
  93         }
  94
  95         printf(HEADER_FORMAT,
  96                 ut->ut_user,
  97                 ut->ut_line,
  98                 show_wide ? INET6_ADDRSTRLEN : INET_ADDRSTRLEN,
  99                 show_wide ? INET6_ADDRSTRLEN : INET_ADDRSTRLEN,
 100                 ut->ut_host,
 101                 login_time,
 102                 logout_str,
 103                 duration_str);
 104 }
 105
 106 static int get_ut_type(struct utmp *ut)
 107 {
 108         if (ut->ut_line[0] == '~') {
 109                 if (strcmp(ut->ut_user, "shutdown") == 0) {
 110                         return SHUTDOWN_TIME;
 111                 }
 112                 if (strcmp(ut->ut_user, "reboot") == 0) {
 113                         return BOOT_TIME;
 114                 }
 115                 if (strcmp(ut->ut_user, "runlevel") == 0) {
 116                         return RUN_LVL;
 117                 }
 118                 return ut->ut_type;
 119         }
 120
 121         if (ut->ut_user[0] == 0) {
 122                 return DEAD_PROCESS;
 123         }
 124
 125         if ((ut->ut_type != DEAD_PROCESS)
 126          && (strcmp(ut->ut_user, "LOGIN") != 0)
 127          && ut->ut_user[0]
 128          && ut->ut_line[0]
 129         ) {
 130                 ut->ut_type = USER_PROCESS;
 131         }
 132
 133         if (strcmp(ut->ut_user, "date") == 0) {
 134                 if (ut->ut_line[0] == '|') {
 135                         return OLD_TIME;
 136                 }
 137                 if (ut->ut_line[0] == '{') {
 138                         return NEW_TIME;
 139                 }
 140         }
 141         return ut->ut_type;
 142 }
 143
 144 static int is_runlevel_shutdown(struct utmp *ut)
 145 {
 146         if (((ut->ut_pid & 255) == '0') || ((ut->ut_pid & 255) == '6')) {
 147                 return 1;
 148         }
 149
 150         return 0;
 151 }
 152
 153 int last_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 154 int last_main(int argc UNUSED_PARAM, char **argv)
 155 {
 156         struct utmp ut;
 157         const char *filename = _PATH_WTMP;
 158         llist_t *zlist;
 159         off_t pos;
 160         time_t start_time;
 161         time_t boot_time;
 162         time_t down_time;
 163         int file;
 164         smallint going_down;
 165         smallint boot_down;
 166
 167         /*opt =*/ getopt32(argv, "Wf:" /* "H" */, &filename);
 168 #ifdef BUT_UTIL_LINUX_LAST_HAS_NO_SUCH_OPT
 169         if (opt & LAST_OPT_H) {
 170                 /* Print header line */
 171                 if (opt & LAST_OPT_W) {
 172                         printf(HEADER_FORMAT, HEADER_LINE_WIDE);
 173                 } else {
 174                         printf(HEADER_FORMAT, HEADER_LINE);
 175                 }
 176         }
 177 #endif
 178
 179         file = xopen(filename, O_RDONLY);
 180         {
 181                 /* in case the file is empty... */
 182                 struct stat st;
 183                 fstat(file, &st);
 184                 start_time = st.st_ctime;
 185         }
 186
 187         time(&down_time);
 188         going_down = 0;
 189         boot_down = NORMAL; /* 0 */
 190         zlist = NULL;
 191         boot_time = 0;
 192         /* get file size, rounding down to last full record */
 193         pos = xlseek(file, 0, SEEK_END) / sizeof(ut) * sizeof(ut);
 194         for (;;) {
 195                 pos -= (off_t)sizeof(ut);
 196                 if (pos < 0) {
 197                         /* Beyond the beginning of the file boundary =>
 198                          * the whole file has been read. */
 199                         break;
 200                 }
 201                 xlseek(file, pos, SEEK_SET);
 202                 xread(file, &ut, sizeof(ut));
 203                 /* rewritten by each record, eventially will have
 204                  * first record's ut_tv.tv_sec: */
 205                 start_time = ut.ut_tv.tv_sec;
 206
 207                 switch (get_ut_type(&ut)) {
 208                 case SHUTDOWN_TIME:
 209                         down_time = ut.ut_tv.tv_sec;
 210                         boot_down = DOWN;
 211                         going_down = 1;
 212                         break;
 213                 case RUN_LVL:
 214                         if (is_runlevel_shutdown(&ut)) {
 215                                 down_time = ut.ut_tv.tv_sec;
 216                                 going_down = 1;
 217                                 boot_down = DOWN;
 218                         }
 219                         break;
 220                 case BOOT_TIME:
 221                         strcpy(ut.ut_line, "system boot");
 222                         show_entry(&ut, REBOOT, down_time);
 223                         boot_down = CRASH;
 224                         going_down = 1;
 225                         break;
 226                 case DEAD_PROCESS:
 227                         if (!ut.ut_line[0]) {
 228                                 break;
 229                         }
 230                         /* add_entry */
 231                         llist_add_to(&zlist, memcpy(xmalloc(sizeof(ut)), &ut, sizeof(ut)));
 232                         break;
 233                 case USER_PROCESS: {
 234                         int show;
 235
 236                         if (!ut.ut_line[0]) {
 237                                 break;
 238                         }
 239                         /* find_entry */
 240                         show = 1;
 241                         {
 242                                 llist_t *el, *next;
 243                                 for (el = zlist; el; el = next) {
 244                                         struct utmp *up = (struct utmp *)el->data;
 245                                         next = el->link;
 246                                         if (strncmp(up->ut_line, ut.ut_line, UT_LINESIZE) == 0) {
 247                                                 if (show) {
 248                                                         show_entry(&ut, NORMAL, up->ut_tv.tv_sec);
 249                                                         show = 0;
 250                                                 }
 251                                                 llist_unlink(&zlist, el);
 252                                                 free(el->data);
 253                                                 free(el);
 254                                         }
 255                                 }
 256                         }
 257
 258                         if (show) {
 259                                 int state = boot_down;
 260
 261                                 if (boot_time == 0) {
 262                                         state = LOGGED;
 263                                         /* Check if the process is alive */
 264                                         if ((ut.ut_pid > 0)
 265                                          && (kill(ut.ut_pid, 0) != 0)
 266                                          && (errno == ESRCH)) {
 267                                                 state = GONE;
 268                                         }
 269                                 }
 270                                 show_entry(&ut, state, boot_time);
 271                         }
 272                         /* add_entry */
 273                         llist_add_to(&zlist, memcpy(xmalloc(sizeof(ut)), &ut, sizeof(ut)));
 274                         break;
 275                 }
 276                 }
 277
 278                 if (going_down) {
 279                         boot_time = ut.ut_tv.tv_sec;
 280                         llist_free(zlist, free);
 281                         zlist = NULL;
 282                         going_down = 0;
 283                 }
 284         }
 285
 286         if (ENABLE_FEATURE_CLEAN_UP) {
 287                 llist_free(zlist, free);
 288         }
 289
 290         printf("\nwtmp begins %s", ctime(&start_time));
 291
 292         if (ENABLE_FEATURE_CLEAN_UP)
 293                 close(file);
 294         fflush_stdout_and_exit(EXIT_SUCCESS);
 295 }