From 30f892a0ee32ec556467e9f7bc7c46d4ed42f12e Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Sun, 25 May 2008 01:14:14 +0000 Subject: [PATCH] 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 --- miscutils/last.c | 5 +++-- miscutils/last_fancy.c | 34 +++++++++++++++++----------------- 2 files changed, 20 insertions(+), 19 deletions(-) diff --git a/miscutils/last.c b/miscutils/last.c index f254118..a84e776 100644 --- 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 --- 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) -- 2.7.4