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authorDenis Vlasenko2008-01-03 12:12:27 +0000
committerDenis Vlasenko2008-01-03 12:12:27 +0000
commit4f2e8bc7656ff64402329de5364ec4502d8007d9 (patch)
tree7f5fbe266b6763d89027c01943a01857e2eb8ef2 /sysklogd
parentfb0eba706cccd510d99c4c5339a76dd15bc8a628 (diff)
downloadbusybox-4f2e8bc7656ff64402329de5364ec4502d8007d9.zip
busybox-4f2e8bc7656ff64402329de5364ec4502d8007d9.tar.gz
syslogd: don't die if remote host's IP cannot be resolved.
retry resolutions every two minutes instead. function old new delta syslogd_main 865 904 +39 timestamp_and_log 324 313 -11 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 1/1 up/down: 39/-11) Total: 28 bytes
Diffstat (limited to 'sysklogd')
-rw-r--r--sysklogd/syslogd.c100
1 files changed, 63 insertions, 37 deletions
diff --git a/sysklogd/syslogd.c b/sysklogd/syslogd.c
index 5998732..7000e93 100644
--- a/sysklogd/syslogd.c
+++ b/sysklogd/syslogd.c
@@ -42,7 +42,10 @@
* (semaphores are down but do_mark routine tries to down them again) */
#undef SYSLOGD_MARK
-enum { MAX_READ = 256 };
+enum {
+ MAX_READ = 256,
+ DNS_WAIT_SEC = 2 * 60,
+};
/* Semaphore operation structures */
struct shbuf_ds {
@@ -86,6 +89,12 @@ struct init_globals {
struct globals {
GLOBALS
+
+#if ENABLE_FEATURE_REMOTE_LOG
+ unsigned last_dns_resolve;
+ char *remoteAddrStr;
+#endif
+
#if ENABLE_FEATURE_IPC_SYSLOG
struct shbuf_ds *shbuf;
#endif
@@ -128,6 +137,9 @@ static const struct init_globals init_data = {
};
#define G (*ptr_to_globals)
+#define INIT_G() do { \
+ PTR_TO_GLOBALS = memcpy(xzalloc(sizeof(G)), &init_data, sizeof(init_data)); \
+} while (0)
/* Options */
@@ -140,7 +152,7 @@ enum {
USE_FEATURE_ROTATE_LOGFILE(OPTBIT_filesize ,) // -s
USE_FEATURE_ROTATE_LOGFILE(OPTBIT_rotatecnt ,) // -b
USE_FEATURE_REMOTE_LOG( OPTBIT_remote ,) // -R
- USE_FEATURE_REMOTE_LOG( OPTBIT_localtoo ,) // -L
+ USE_FEATURE_REMOTE_LOG( OPTBIT_locallog ,) // -L
USE_FEATURE_IPC_SYSLOG( OPTBIT_circularlog,) // -C
OPT_mark = 1 << OPTBIT_mark ,
@@ -151,7 +163,7 @@ enum {
OPT_filesize = USE_FEATURE_ROTATE_LOGFILE((1 << OPTBIT_filesize )) + 0,
OPT_rotatecnt = USE_FEATURE_ROTATE_LOGFILE((1 << OPTBIT_rotatecnt )) + 0,
OPT_remotelog = USE_FEATURE_REMOTE_LOG( (1 << OPTBIT_remote )) + 0,
- OPT_locallog = USE_FEATURE_REMOTE_LOG( (1 << OPTBIT_localtoo )) + 0,
+ OPT_locallog = USE_FEATURE_REMOTE_LOG( (1 << OPTBIT_locallog )) + 0,
OPT_circularlog = USE_FEATURE_IPC_SYSLOG( (1 << OPTBIT_circularlog)) + 0,
};
#define OPTION_STR "m:nO:l:S" \
@@ -163,12 +175,11 @@ enum {
#define OPTION_DECL *opt_m, *opt_l \
USE_FEATURE_ROTATE_LOGFILE(,*opt_s) \
USE_FEATURE_ROTATE_LOGFILE(,*opt_b) \
- USE_FEATURE_REMOTE_LOG( ,*opt_R) \
USE_FEATURE_IPC_SYSLOG( ,*opt_C = NULL)
#define OPTION_PARAM &opt_m, &G.logFilePath, &opt_l \
USE_FEATURE_ROTATE_LOGFILE(,&opt_s) \
USE_FEATURE_ROTATE_LOGFILE(,&opt_b) \
- USE_FEATURE_REMOTE_LOG( ,&opt_R) \
+ USE_FEATURE_REMOTE_LOG( ,&G.remoteAddrStr) \
USE_FEATURE_IPC_SYSLOG( ,&opt_C)
@@ -387,6 +398,9 @@ static void timestamp_and_log(int pri, char *msg, int len)
{
char *timestamp;
+ if (ENABLE_FEATURE_REMOTE_LOG && !(option_mask32 & OPT_locallog))
+ return;
+
if (len < 16 || msg[3] != ' ' || msg[6] != ' '
|| msg[9] != ':' || msg[12] != ':' || msg[15] != ' '
) {
@@ -400,18 +414,14 @@ static void timestamp_and_log(int pri, char *msg, int len)
timestamp[15] = '\0';
/* Log message locally (to file or shared mem) */
- if (!ENABLE_FEATURE_REMOTE_LOG || (option_mask32 & OPT_locallog)) {
- if (LOG_PRI(pri) < G.logLevel) {
- if (option_mask32 & OPT_small)
- sprintf(G.printbuf, "%s %s\n", timestamp, msg);
- else {
- char res[20];
- parse_fac_prio_20(pri, res);
- sprintf(G.printbuf, "%s %s %s %s\n", timestamp, G.localHostName, res, msg);
- }
- log_locally(G.printbuf);
- }
+ if (option_mask32 & OPT_small)
+ sprintf(G.printbuf, "%s %s\n", timestamp, msg);
+ else {
+ char res[20];
+ parse_fac_prio_20(pri, res);
+ sprintf(G.printbuf, "%s %s %s %s\n", timestamp, G.localHostName, res, msg);
}
+ log_locally(G.printbuf);
}
static void split_escape_and_log(char *tmpbuf, int len)
@@ -443,8 +453,10 @@ static void split_escape_and_log(char *tmpbuf, int len)
*q++ = c;
}
*q = '\0';
+
/* Now log it */
- timestamp_and_log(pri, G.parsebuf, q - G.parsebuf);
+ if (LOG_PRI(pri) < G.logLevel)
+ timestamp_and_log(pri, G.parsebuf, q - G.parsebuf);
}
}
@@ -495,6 +507,24 @@ static NOINLINE int create_socket(void)
return sock_fd;
}
+#if ENABLE_FEATURE_REMOTE_LOG
+static int try_to_resolve_remote(void)
+{
+ if (!G.remoteAddr) {
+ unsigned now = monotonic_sec();
+
+ /* Don't resolve name too often - DNS timeouts can be big */
+ if ((now - G.last_dns_resolve) < DNS_WAIT_SEC)
+ return -1;
+ G.last_dns_resolve = now;
+ G.remoteAddr = host2sockaddr(G.remoteAddrStr, 514);
+ if (!G.remoteAddr)
+ return -1;
+ }
+ return socket(G.remoteAddr->sa.sa_family, SOCK_DGRAM, 0);
+}
+#endif
+
static void do_syslogd(void) ATTRIBUTE_NORETURN;
static void do_syslogd(void)
{
@@ -505,10 +535,7 @@ static void do_syslogd(void)
signal(SIGTERM, quit_signal);
signal(SIGQUIT, quit_signal);
signal(SIGHUP, SIG_IGN);
- signal(SIGCHLD, SIG_IGN);
-#ifdef SIGCLD
- signal(SIGCLD, SIG_IGN);
-#endif
+ /* signal(SIGCHLD, SIG_IGN); - why? */
#ifdef SYSLOGD_MARK
signal(SIGALRM, do_mark);
alarm(G.markInterval);
@@ -554,19 +581,21 @@ static void do_syslogd(void)
#if ENABLE_FEATURE_REMOTE_LOG
/* We are not modifying log messages in any way before send */
/* Remote site cannot trust _us_ anyway and need to do validation again */
- if (G.remoteAddr) {
+ if (G.remoteAddrStr) {
if (-1 == G.remoteFD) {
- G.remoteFD = socket(G.remoteAddr->sa.sa_family, SOCK_DGRAM, 0);
- }
- if (-1 != G.remoteFD) {
- /* send message to remote logger, ignore possible error */
- sendto(G.remoteFD, G.recvbuf, sz, MSG_DONTWAIT,
- &G.remoteAddr->sa, G.remoteAddr->len);
+ G.remoteFD = try_to_resolve_remote();
+ if (-1 == G.remoteFD)
+ goto no_luck;
}
+ /* send message to remote logger, ignore possible error */
+ sendto(G.remoteFD, G.recvbuf, sz, MSG_DONTWAIT,
+ &G.remoteAddr->sa, G.remoteAddr->len);
+ no_luck: ;
}
#endif
- split_escape_and_log(G.recvbuf, sz);
- } /* for */
+ if (!ENABLE_FEATURE_REMOTE_LOG || (option_mask32 & OPT_locallog))
+ split_escape_and_log(G.recvbuf, sz);
+ } /* for (;;) */
}
int syslogd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
@@ -575,7 +604,10 @@ int syslogd_main(int argc, char **argv)
char OPTION_DECL;
char *p;
- PTR_TO_GLOBALS = memcpy(xzalloc(sizeof(G)), &init_data, sizeof(init_data));
+ INIT_G();
+#if ENABLE_FEATURE_REMOTE_LOG
+ G.last_dns_resolve = monotonic_sec() - DNS_WAIT_SEC - 1;
+#endif
/* do normal option parsing */
opt_complementary = "=0"; /* no non-option params */
@@ -595,12 +627,6 @@ int syslogd_main(int argc, char **argv)
if (option_mask32 & OPT_rotatecnt) // -b
G.logFileRotate = xatou_range(opt_b, 0, 99);
#endif
-#if ENABLE_FEATURE_REMOTE_LOG
- if (option_mask32 & OPT_remotelog) { // -R
- G.remoteAddr = xhost2sockaddr(opt_R, 514);
- }
- //if (option_mask32 & OPT_locallog) // -L
-#endif
#if ENABLE_FEATURE_IPC_SYSLOG
if (opt_C) // -Cn
G.shm_size = xatoul_range(opt_C, 4, INT_MAX/1024) * 1024;