* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
-#include <stdio.h>
-#include <stdlib.h>
-#include <signal.h> /* for our signal() handlers */
-#include <string.h> /* strncpy() */
-#include <errno.h> /* errno and friends */
-#include <unistd.h>
-#include <ctype.h>
-#include <sys/syslog.h>
+#include "libbb.h"
+#include <syslog.h>
#include <sys/klog.h>
-#include "busybox.h"
-
static void klogd_signal(int sig)
{
- klogctl(7, NULL, 0);
- klogctl(0, 0, 0);
- /* logMessage(0, "Kernel log daemon exiting."); */
- syslog(LOG_NOTICE, "Kernel log daemon exiting.");
- exit(EXIT_SUCCESS);
+ /* 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 doKlogd(const int console_log_level) ATTRIBUTE_NORETURN;
-static void doKlogd(const int console_log_level)
+#define log_buffer bb_common_bufsiz1
+enum {
+ KLOGD_LOGBUF_SIZE = sizeof(log_buffer),
+ OPT_LEVEL = (1 << 0),
+ OPT_FOREGROUND = (1 << 1),
+};
+
+int klogd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int klogd_main(int argc UNUSED_PARAM, char **argv)
{
- int priority = LOG_INFO;
- char log_buffer[4096];
- int i, n, lastc;
- char *start;
+ int i = 0;
+ char *opt_c;
+ int opt;
+ int used = 0;
+
+ 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);
+ }
openlog("kernel", 0, LOG_KERN);
- /* Set up sig handlers */
- signal(SIGINT, klogd_signal);
- signal(SIGKILL, klogd_signal);
- signal(SIGTERM, klogd_signal);
+ bb_signals(BB_FATAL_SIGS, klogd_signal);
signal(SIGHUP, SIG_IGN);
- /* "Open the log. Currently a NOP." */
+ /* "Open the log. Currently a NOP" */
klogctl(1, NULL, 0);
- /* Set level of kernel console messaging.. */
- if (console_log_level != -1)
- klogctl(8, NULL, console_log_level);
+ /* "printk() prints a message on the console only if it has a loglevel
+ * less than console_loglevel". Here we set console_loglevel = i. */
+ if (i)
+ klogctl(8, NULL, i);
- syslog(LOG_NOTICE, "klogd started: %s", BB_BANNER);
+ syslog(LOG_NOTICE, "klogd started: %s", bb_banner);
while (1) {
- /* Use kernel syscalls */
- memset(log_buffer, '\0', sizeof(log_buffer));
- n = klogctl(2, log_buffer, sizeof(log_buffer));
+ int n;
+ int priority;
+ char *start;
+
+ /* "2 -- Read from the log." */
+ start = log_buffer + used;
+ n = klogctl(2, start, KLOGD_LOGBUF_SIZE-1 - used);
if (n < 0) {
if (errno == EINTR)
continue;
- syslog(LOG_ERR, "klogd: Error return from sys_sycall: %d - %m.\n", errno);
- exit(EXIT_FAILURE);
+ syslog(LOG_ERR, "klogd: error %d in klogctl(2): %m",
+ errno);
+ break;
}
+ start[n] = '\0';
/* klogctl buffer parsing modelled after code in dmesg.c */
- start = &log_buffer[0];
- lastc = '\0';
- for (i = 0; i < n; i++) {
- if (lastc == '\0' && log_buffer[i] == '<') {
- priority = 0;
- i++;
- while (isdigit(log_buffer[i])) {
- priority = priority * 10 + (log_buffer[i] - '0');
- i++;
+ /* 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... */
+ if (start != log_buffer) {
+ /* move it to the front of the buffer */
+ overlapping_strcpy(log_buffer, start);
+ used = newline - start;
+ /* don't log it yet */
+ break;
}
- if (log_buffer[i] == '>')
- i++;
- start = &log_buffer[i];
- }
- if (log_buffer[i] == '\n') {
- log_buffer[i] = '\0'; /* zero terminate this message */
- syslog(priority, "%s", start);
- start = &log_buffer[i + 1];
- priority = LOG_INFO;
+ /* ...but if buffer is full, log it anyway */
+ used = 0;
+ newline = NULL;
+ } else {
+ *newline++ = '\0';
}
- lastc = log_buffer[i];
- }
- }
-}
-
-#define OPT_LEVEL 1
-#define OPT_FOREGROUND 2
-
-int klogd_main(int argc, char **argv)
-{
- unsigned long opt;
- char *c_arg;
- int console_log_level = -1;
- /* do normal option parsing */
- opt = bb_getopt_ulflags (argc, argv, "c:n", &c_arg);
-
- if (opt & OPT_LEVEL) {
- /* Valid levels are between 1 and 8 */
- console_log_level = bb_xgetlarg(c_arg, 10, 1, 8);
- }
+ /* 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);
- if (!(opt & OPT_FOREGROUND)) {
-#ifdef BB_NOMMU
- vfork_daemon_rexec(0, 1, argc, argv, "-n");
-#else
- bb_xdaemon(0, 1);
-#endif
+ if (!newline)
+ break;
+ start = newline;
+ }
}
- doKlogd(console_log_level);
- return EXIT_SUCCESS;
+ return EXIT_FAILURE;
}
projects / oweals / busybox.git / blobdiff