static void klogd_signal(int sig ATTRIBUTE_UNUSED)
{
klogctl(7, NULL, 0);
klogctl(0, NULL, 0);
syslog(LOG_NOTICE, "klogd: exiting");
kill_myself_with_sig(sig);
}
static void cleanup(int code)
{
remove_pidfile(pidfile);
if (code > EXIT_FAILURE)
kill_myself_with_sig(code);
exit(code);
}
/* Exit the program gracefully */
static void less_exit(int code)
{
set_tty_cooked();
clear_line();
if (code < 0)
kill_myself_with_sig(- code); /* does not return */
exit(code);
}
/* Exit the program gracefully */
static void less_exit(int code)
{
bb_putchar('\n');
set_tty_cooked();
if (code < 0)
kill_myself_with_sig(- code); /* does not return */
exit(code);
}
static void klogd_signal(int sig)
{
/* FYI: cmd 7 is equivalent to setting console_loglevel to 7
* via klogctl(8, NULL, 7). */
klogctl(7, NULL, 0); /* "7 -- Enable printk's to console" */
klogctl(0, NULL, 0); /* "0 -- Close the log. Currently a NOP" */
syslog(LOG_NOTICE, "klogd: exiting");
kill_myself_with_sig(sig);
}
static void cleanup(int code)
{
set_cursor(CURSOR_ON);
tcsetattr(G.kbd_fd, TCSANOW, &G.term_orig);
if (ENABLE_FEATURE_CLEAN_UP) {
close(G.kbd_fd);
}
// Reset attributes
if (!BW)
putcsi("0m");
bb_putchar('\n');
if (code > EXIT_FAILURE)
kill_myself_with_sig(code);
exit(code);
}
static void cleanup(int code)
{
set_cursor(-1); // cursor on
tcsetattr(G.kbd_fd, TCSANOW, &G.term_orig);
if (ENABLE_FEATURE_CLEAN_UP) {
close(G.kbd_fd);
}
// Reset attributes
if (!BW)
fputs("\033[0m", stdout);
bb_putchar('\n');
if (code > 1)
kill_myself_with_sig(code);
exit(code);
}
int klogd_main(int argc UNUSED_PARAM, char **argv)
{
int i = 0;
char *opt_c;
int opt;
int used;
unsigned int cnt;
opt = getopt32(argv, "c:n", &opt_c);
if (opt & OPT_LEVEL) {
/* Valid levels are between 1 and 8 */
i = xatou_range(opt_c, 1, 8);
}
if (!(opt & OPT_FOREGROUND)) {
bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv);
}
logmode = LOGMODE_SYSLOG;
/* klogd_open() before openlog(), since it might use fixed fd 3,
* and openlog() also may use the same fd 3 if we swap them:
*/
klogd_open();
openlog("kernel", 0, LOG_KERN);
/*
* glibc problem: for some reason, glibc changes LOG_KERN to LOG_USER
* above. The logic behind this is that standard
* http://pubs.opengroup.org/onlinepubs/9699919799/functions/syslog.html
* says the following about openlog and syslog:
* "LOG_USER
* Messages generated by arbitrary processes.
* This is the default facility identifier if none is specified."
*
* I believe glibc misinterpreted this text as "if openlog's
* third parameter is 0 (=LOG_KERN), treat it as LOG_USER".
* Whereas it was meant to say "if *syslog* is called with facility
* 0 in its 1st parameter without prior call to openlog, then perform
* implicit openlog(LOG_USER)".
*
* As a result of this, eh, feature, standard klogd was forced
* to open-code its own openlog and syslog implementation (!).
*
* Note that prohibiting openlog(LOG_KERN) on libc level does not
* add any security: any process can open a socket to "/dev/log"
* and write a string "<0>Voila, a LOG_KERN + LOG_EMERG message"
*
* Google code search tells me there is no widespread use of
* openlog("foo", 0, 0), thus fixing glibc won't break userspace.
*
* The bug against glibc was filed:
* bugzilla.redhat.com/show_bug.cgi?id=547000
*/
if (i)
klogd_setloglevel(i);
signal(SIGHUP, SIG_IGN);
/* We want klogd_read to not be restarted, thus _norestart: */
bb_signals_recursive_norestart(BB_FATAL_SIGS, record_signo);
syslog(LOG_NOTICE, "klogd started: %s", bb_banner);
used = 0;
cnt = 0;
while (!bb_got_signal) {
int n;
int priority;
char *start;
char *eor;
/* "2 -- Read from the log." */
start = log_buffer + used;
n = klogd_read(start, KLOGD_LOGBUF_SIZE-1 - used);
if (n < 0) {
if (errno == EINTR)
continue;
bb_perror_msg(READ_ERROR);
break;
}
start[n] = '\0';
eor = &start[n];
/* Process each newline-terminated line in the buffer */
start = log_buffer;
while (1) {
char *newline = strchrnul(start, '\n');
if (*newline == '\0') {
/* This line is incomplete */
/* move it to the front of the buffer */
overlapping_strcpy(log_buffer, start);
used = newline - start;
if (used < KLOGD_LOGBUF_SIZE-1) {
/* buffer isn't full */
break;
}
/* buffer is full, log it anyway */
used = 0;
newline = NULL;
} else {
*newline++ = '\0';
}
/* Extract the priority */
priority = LOG_INFO;
if (*start == '<') {
start++;
if (*start) {
/* kernel never generates multi-digit prios */
priority = (*start - '0');
start++;
}
if (*start == '>')
start++;
}
/* Log (only non-empty lines) */
if (*start) {
syslog(priority, "%s", start);
/* give syslog time to catch up */
++cnt;
if ((cnt & 0x07) == 0 && (cnt < 300 || (eor - start) > 200))
usleep(50 * 1000);
}
if (!newline)
break;
start = newline;
}
}
klogd_close();
syslog(LOG_NOTICE, "klogd: exiting");
if (bb_got_signal)
kill_myself_with_sig(bb_got_signal);
return EXIT_FAILURE;
}
static void term_handler(int sig)
{
cleanup();
kill_myself_with_sig(sig);
}
static void sig_term_handler(int sig)
{
if (verbose)
bb_error_msg("got signal %u, exit", sig);
kill_myself_with_sig(sig);
}