last: code shrink

function                                             old     new   delta
show_entry                                           319     311      -8
last_main                                            917     907     -10
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-18)             Total: -18 bytes
This commit is contained in:
Denis Vlasenko 2008-05-25 01:14:14 +00:00
parent 69dc325397
commit 30f892a0ee
2 changed files with 20 additions and 19 deletions

View File

@ -118,9 +118,10 @@ int last_main(int argc, char **argv ATTRIBUTE_UNUSED)
printf("%-10s %-14s %-18s %-12.12s\n",
ut.ut_user, ut.ut_line, ut.ut_host, ctime(&t_tmp) + 4);
next:
if (!pos)
pos -= sizeof(ut);
if (pos <= 0)
break; /* done. */
pos = lseek(file, pos - sizeof(ut), SEEK_SET);
xlseek(file, pos, SEEK_SET);
}
fflush_stdout_and_exit(EXIT_SUCCESS);

View File

@ -57,11 +57,11 @@ static void show_entry(struct utmp *ut, int state, time_t dur_secs)
hours = mins / 60;
mins = mins % 60;
if (days) {
// if (days) {
sprintf(duration, "(%u+%02u:%02u)", days, hours, mins);
} else {
sprintf(duration, " (%02u:%02u)", hours, mins);
}
// } else {
// sprintf(duration, " (%02u:%02u)", hours, mins);
// }
logout_str = logout_time;
duration_str = duration;
@ -100,13 +100,13 @@ static void show_entry(struct utmp *ut, int state, time_t dur_secs)
static int get_ut_type(struct utmp *ut)
{
if (ut->ut_line[0] == '~') {
if (strncmp(ut->ut_user, "shutdown", sizeof("shutdown")-1) == 0) {
if (strcmp(ut->ut_user, "shutdown") == 0) {
return SHUTDOWN_TIME;
}
if (strncmp(ut->ut_user, "reboot", sizeof("reboot")-1) == 0) {
if (strcmp(ut->ut_user, "reboot") == 0) {
return BOOT_TIME;
}
if (strncmp(ut->ut_user, "runlevel", sizeof("runlevel")-1) == 0) {
if (strcmp(ut->ut_user, "runlevel") == 0) {
return RUN_LVL;
}
return ut->ut_type;
@ -172,31 +172,32 @@ int last_main(int argc ATTRIBUTE_UNUSED, char **argv)
#endif
file = xopen(filename, O_RDONLY);
if (full_read(file, &ut, sizeof(ut)) != sizeof(ut)) {
{
/* in case the file is empty... */
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;
/* get file size, rounding down to last full record */
pos = xlseek(file, 0, SEEK_END) / sizeof(ut) * sizeof(ut);
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) {
if (pos < 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;
xlseek(file, pos, SEEK_SET);
xread(file, &ut, sizeof(ut));
/* rewritten by each record, eventially will have
* first record's ut_time: */
start_time = ut.ut_time;
switch (get_ut_type(&ut)) {
case SHUTDOWN_TIME:
@ -281,7 +282,6 @@ int last_main(int argc ATTRIBUTE_UNUSED, char **argv)
llist_free(zlist, free);
}
exit:
printf("\nwtmp begins %s", ctime(&start_time));
if (ENABLE_FEATURE_CLEAN_UP)