last: optional alternative sysv-like implementation

(by Patricia Muscalu <patricia.muscalu AT axis.com>)

function                                             old     new   delta
last_main                                            448     917    +469
show_entry                                             -     319    +319
packed_usage                                       24216   24268     +52
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 2/0 up/down: 840/0)             Total: 840 bytes
This commit is contained in:
Denis Vlasenko 2008-05-22 02:07:58 +00:00
parent 7bd8d8fd26
commit 869d3d318f
4 changed files with 307 additions and 2 deletions

View File

@ -3504,9 +3504,15 @@
"lash is deprecated, please use hush"
#define last_trivial_usage \
""
""USE_FEATURE_LAST_FANCY("[-HW] [-f file]")
#define last_full_usage "\n\n" \
"Show listing of the last users that logged into the system"
"Show listing of the last users that logged into the system" \
USE_FEATURE_LAST_FANCY( "\n" \
"\nOptions:" \
"\n -H Show header line" \
"\n -W Display with no host column truncation" \
"\n -f file Read from file instead of /var/log/wtmp" \
)
#define sha1sum_trivial_usage \
"[OPTION] [FILEs...]" \

View File

@ -229,6 +229,14 @@ config LAST
help
'last' displays a list of the last users that logged into the system.
config FEATURE_LAST_FANCY
bool "Fancy output"
default n
depends on LAST
help
'last' displays detailed information about the last users that
logged into the system (mimics sysvinit last). +900 bytes.
config LESS
bool "less"
default n

View File

@ -26,6 +26,12 @@
#error struct utmp member char[] size(s) have changed!
#endif
#if ENABLE_FEATURE_LAST_FANCY
#include "last_fancy.c"
#else
int last_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int last_main(int argc, char **argv ATTRIBUTE_UNUSED)
{
@ -92,3 +98,5 @@ int last_main(int argc, char **argv ATTRIBUTE_UNUSED)
fflush_stdout_and_exit(EXIT_SUCCESS);
}
#endif

283
miscutils/last_fancy.c Normal file
View File

@ -0,0 +1,283 @@
/* 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);
}