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

diff --git a/miscutils/last.c b/miscutils/last.c
index f254118..a84e776 100644 (file)
--- a/miscutils/last.c
+++ b/miscutils/last.c
@@ -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);

diff --git a/miscutils/last_fancy.c b/miscutils/last_fancy.c
index 91315d3..d234a48 100644 (file)
--- a/miscutils/last_fancy.c
+++ b/miscutils/last_fancy.c
@@ -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)