--- /dev/null
+/* vi: set sw=4 ts=4: */
+/*
+ * (sysvinit like) last implementation
+ *
+ * Copyright (C) 2008 by Patricia Muscalu <patricia.muscalu@axis.com>
+ *
+ * Licensed under the GPLv2 or later, see the file LICENSE in this tarball.
+ */
+
+#define HEADER_FORMAT "%-8.8s %-12.12s %-*.*s %-16.16s %-7.7s %-12.12s\n"
+#define HEADER_LINE "USER", "TTY", \
+ INET_ADDRSTRLEN, INET_ADDRSTRLEN, "HOST", "LOGIN", " TIME", ""
+#define HEADER_LINE_WIDE "USER", "TTY", \
+ INET6_ADDRSTRLEN, INET6_ADDRSTRLEN, "HOST", "LOGIN", " TIME", ""
+
+enum {
+ NORMAL,
+ LOGGED,
+ DOWN,
+ REBOOT,
+ CRASH,
+ GONE
+};
+
+enum {
+ LAST_OPT_W = (1 << 0), /* -W wide */
+ LAST_OPT_f = (1 << 1), /* -f input file */
+ LAST_OPT_H = (1 << 2), /* -H header */
+};
+
+#define show_wide (option_mask32 & LAST_OPT_W)
+
+static void show_entry(struct utmp *ut, int state, time_t dur_secs)
+{
+ unsigned days, hours, mins;
+ char duration[32];
+ char login_time[17];
+ char logout_time[8];
+ const char *logout_str;
+ const char *duration_str;
+
+ safe_strncpy(login_time, ctime(&(ut->ut_time)), 17);
+ snprintf(logout_time, 8, "- %s", ctime(&dur_secs) + 11);
+
+ dur_secs = MAX(dur_secs - (time_t)ut->ut_tv.tv_sec, (time_t)0);
+ /* unsigned int is easier to divide than time_t (which may be signed long) */
+ mins = dur_secs / 60;
+ days = mins / (24*60);
+ mins = mins % (24*60);
+ hours = mins / 60;
+ mins = mins % 60;
+
+ if (days) {
+ sprintf(duration, "(%u+%02u:%02u)", days, hours, mins);
+ } else {
+ sprintf(duration, " (%02u:%02u)", hours, mins);
+ }
+
+ logout_str = logout_time;
+ duration_str = duration;
+ switch (state) {
+ case NORMAL:
+ break;
+ case LOGGED:
+ logout_str = " still";
+ duration_str = "logged in";
+ break;
+ case DOWN:
+ logout_str = "- down ";
+ break;
+ case REBOOT:
+ break;
+ case CRASH:
+ logout_str = "- crash";
+ break;
+ case GONE:
+ logout_str = " gone";
+ duration_str = "- no logout";
+ break;
+ }
+
+ printf(HEADER_FORMAT,
+ ut->ut_name,
+ ut->ut_line,
+ show_wide ? INET6_ADDRSTRLEN : INET_ADDRSTRLEN,
+ show_wide ? INET6_ADDRSTRLEN : INET_ADDRSTRLEN,
+ ut->ut_host,
+ login_time,
+ logout_str,
+ duration_str);
+}
+
+static int get_ut_type(struct utmp *ut)
+{
+ if (ut->ut_line[0] == '~') {
+ if (strncmp(ut->ut_user, "shutdown", sizeof("shutdown")-1) == 0) {
+ return SHUTDOWN_TIME;
+ }
+ if (strncmp(ut->ut_user, "reboot", sizeof("reboot")-1) == 0) {
+ return BOOT_TIME;
+ }
+ if (strncmp(ut->ut_user, "runlevel", sizeof("runlevel")-1) == 0) {
+ return RUN_LVL;
+ }
+ return ut->ut_type;
+ }
+
+ if (ut->ut_name[0] == 0) {
+ return DEAD_PROCESS;
+ }
+
+ if ((ut->ut_type != DEAD_PROCESS)
+ && (strcmp(ut->ut_name, "LOGIN") != 0)
+ && ut->ut_name[0]
+ && ut->ut_line[0]
+ ) {
+ ut->ut_type = USER_PROCESS;
+ }
+
+ if (strcmp(ut->ut_name, "date") == 0) {
+ if (ut->ut_line[0] == '|') {
+ return OLD_TIME;
+ }
+ if (ut->ut_line[0] == '{') {
+ return NEW_TIME;
+ }
+ }
+ return ut->ut_type;
+}
+
+static int is_runlevel_shutdown(struct utmp *ut)
+{
+ if (((ut->ut_pid & 255) == '0') || ((ut->ut_pid & 255) == '6')) {
+ return 1;
+ }
+
+ return 0;
+}
+
+int last_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int last_main(int argc ATTRIBUTE_UNUSED, char **argv)
+{
+ struct utmp ut;
+ const char *filename = _PATH_WTMP;
+ llist_t *zlist;
+ off_t pos;
+ time_t start_time;
+ time_t boot_time;
+ time_t down_time;
+ int file;
+ unsigned opt;
+ smallint going_down;
+ smallint boot_down;
+
+ opt = getopt32(argv, "Wf:" /* "H" */, &filename);
+#ifdef BUT_UTIL_LINUX_LAST_HAS_NO_SUCH_OPT
+ if (opt & LAST_OPT_H) {
+ /* Print header line */
+ if (opt & LAST_OPT_W) {
+ printf(HEADER_FORMAT, HEADER_LINE_WIDE);
+ } else {
+ printf(HEADER_FORMAT, HEADER_LINE);
+ }
+ }
+#endif
+
+ file = xopen(filename, O_RDONLY);
+ if (full_read(file, &ut, sizeof(ut)) != sizeof(ut)) {
+ struct stat st;
+ fstat(file, &st);
+ start_time = st.st_ctime;
+ goto exit;
+ }
+ start_time = ut.ut_time;
+
+ time(&down_time);
+ going_down = 0;
+ boot_down = NORMAL; /* 0 */
+ zlist = NULL;
+ boot_time = 0;
+ pos = 0;
+ for (;;) {
+ pos -= (off_t)sizeof(ut);
+ /* Bug? What if file changes size?
+ * What if size is not a multiple of sizeof(ut)? */
+ if (lseek(file, pos, SEEK_END) < 0) {
+ /* Beyond the beginning of the file boundary =>
+ * the whole file has been read. */
+ break;
+ }
+ if (full_read(file, &ut, sizeof(ut)) != sizeof(ut))
+ break;
+
+ switch (get_ut_type(&ut)) {
+ case SHUTDOWN_TIME:
+ down_time = ut.ut_time;
+ boot_down = DOWN;
+ going_down = 1;
+ break;
+ case RUN_LVL:
+ if (is_runlevel_shutdown(&ut)) {
+ down_time = ut.ut_time;
+ going_down = 1;
+ boot_down = DOWN;
+ }
+ break;
+ case BOOT_TIME:
+ strcpy(ut.ut_line, "system boot");
+ show_entry(&ut, REBOOT, down_time);
+ boot_down = CRASH;
+ going_down = 1;
+ break;
+ case DEAD_PROCESS:
+ if (!ut.ut_line[0]) {
+ break;
+ }
+ /* add_entry */
+ llist_add_to(&zlist, memcpy(xmalloc(sizeof(ut)), &ut, sizeof(ut)));
+ break;
+ case USER_PROCESS: {
+ int show;
+
+ if (!ut.ut_line[0]) {
+ break;
+ }
+ /* find_entry */
+ show = 1;
+ {
+ llist_t *el, *next;
+ for (el = zlist; el; el = next) {
+ struct utmp *up = (struct utmp *)el->data;
+ next = el->link;
+ if (strncmp(up->ut_line, ut.ut_line, UT_LINESIZE) == 0) {
+ if (show) {
+ show_entry(&ut, NORMAL, up->ut_time);
+ show = 0;
+ }
+ llist_unlink(&zlist, el);
+ free(el->data);
+ free(el);
+ }
+ }
+ }
+
+ if (show) {
+ int state = boot_down;
+
+ if (boot_time == 0) {
+ state = LOGGED;
+ /* Check if the process is alive */
+ if ((ut.ut_pid > 0)
+ && (kill(ut.ut_pid, 0) != 0)
+ && (errno == ESRCH)) {
+ state = GONE;
+ }
+ }
+ show_entry(&ut, state, boot_time);
+ }
+ /* add_entry */
+ llist_add_to(&zlist, memcpy(xmalloc(sizeof(ut)), &ut, sizeof(ut)));
+ break;
+ }
+ }
+
+ if (going_down) {
+ boot_time = ut.ut_time;
+ llist_free(zlist, free);
+ zlist = NULL;
+ going_down = 0;
+ }
+ }
+
+ if (ENABLE_FEATURE_CLEAN_UP) {
+ llist_free(zlist, free);
+ }
+
+ exit:
+ printf("\nwtmp begins %s", ctime(&start_time));
+
+ if (ENABLE_FEATURE_CLEAN_UP)
+ close(file);
+ fflush_stdout_and_exit(EXIT_SUCCESS);
+}