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syslogd: don't die if remote host's IP cannot be resolved.

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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
This commit is contained in:
Denis Vlasenko 2008-01-03 12:12:27 +00:00
parent fb0eba706c
commit 4f2e8bc765
1 changed files with 63 additions and 37 deletions
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100
sysklogd/syslogd.c
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@ -42,7 +42,10 @@
* (semaphores are down but do_mark routine tries to down them again) */ * (semaphores are down but do_mark routine tries to down them again) */
#undef SYSLOGD_MARK #undef SYSLOGD_MARK
enum { MAX_READ = 256 }; enum {
MAX_READ = 256,
DNS_WAIT_SEC = 2 * 60,
};
/* Semaphore operation structures */ /* Semaphore operation structures */
struct shbuf_ds { struct shbuf_ds {
@ -86,6 +89,12 @@ struct init_globals {
struct globals { struct globals {
GLOBALS GLOBALS
#if ENABLE_FEATURE_REMOTE_LOG
unsigned last_dns_resolve;
char *remoteAddrStr;
#endif
#if ENABLE_FEATURE_IPC_SYSLOG #if ENABLE_FEATURE_IPC_SYSLOG
struct shbuf_ds *shbuf; struct shbuf_ds *shbuf;
#endif #endif
@ -128,6 +137,9 @@ static const struct init_globals init_data = {
}; };
#define G (*ptr_to_globals) #define G (*ptr_to_globals)
#define INIT_G() do { \
PTR_TO_GLOBALS = memcpy(xzalloc(sizeof(G)), &init_data, sizeof(init_data)); \
} while (0)
/* Options */ /* Options */
@ -140,7 +152,7 @@ enum {
USE_FEATURE_ROTATE_LOGFILE(OPTBIT_filesize ,) // -s USE_FEATURE_ROTATE_LOGFILE(OPTBIT_filesize ,) // -s
USE_FEATURE_ROTATE_LOGFILE(OPTBIT_rotatecnt ,) // -b USE_FEATURE_ROTATE_LOGFILE(OPTBIT_rotatecnt ,) // -b
USE_FEATURE_REMOTE_LOG( OPTBIT_remote ,) // -R 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 USE_FEATURE_IPC_SYSLOG( OPTBIT_circularlog,) // -C
OPT_mark = 1 << OPTBIT_mark , OPT_mark = 1 << OPTBIT_mark ,
@ -151,7 +163,7 @@ enum {
OPT_filesize = USE_FEATURE_ROTATE_LOGFILE((1 << OPTBIT_filesize )) + 0, OPT_filesize = USE_FEATURE_ROTATE_LOGFILE((1 << OPTBIT_filesize )) + 0,
OPT_rotatecnt = USE_FEATURE_ROTATE_LOGFILE((1 << OPTBIT_rotatecnt )) + 0, OPT_rotatecnt = USE_FEATURE_ROTATE_LOGFILE((1 << OPTBIT_rotatecnt )) + 0,
OPT_remotelog = USE_FEATURE_REMOTE_LOG( (1 << OPTBIT_remote )) + 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, OPT_circularlog = USE_FEATURE_IPC_SYSLOG( (1 << OPTBIT_circularlog)) + 0,
}; };
#define OPTION_STR "m:nO:l:S" \ #define OPTION_STR "m:nO:l:S" \
@ -163,12 +175,11 @@ enum {
#define OPTION_DECL *opt_m, *opt_l \ #define OPTION_DECL *opt_m, *opt_l \
USE_FEATURE_ROTATE_LOGFILE(,*opt_s) \ USE_FEATURE_ROTATE_LOGFILE(,*opt_s) \
USE_FEATURE_ROTATE_LOGFILE(,*opt_b) \ USE_FEATURE_ROTATE_LOGFILE(,*opt_b) \
USE_FEATURE_REMOTE_LOG( ,*opt_R) \
USE_FEATURE_IPC_SYSLOG( ,*opt_C = NULL) USE_FEATURE_IPC_SYSLOG( ,*opt_C = NULL)
#define OPTION_PARAM &opt_m, &G.logFilePath, &opt_l \ #define OPTION_PARAM &opt_m, &G.logFilePath, &opt_l \
USE_FEATURE_ROTATE_LOGFILE(,&opt_s) \ USE_FEATURE_ROTATE_LOGFILE(,&opt_s) \
USE_FEATURE_ROTATE_LOGFILE(,&opt_b) \ USE_FEATURE_ROTATE_LOGFILE(,&opt_b) \
USE_FEATURE_REMOTE_LOG( ,&opt_R) \ USE_FEATURE_REMOTE_LOG( ,&G.remoteAddrStr) \
USE_FEATURE_IPC_SYSLOG( ,&opt_C) USE_FEATURE_IPC_SYSLOG( ,&opt_C)
@ -387,6 +398,9 @@ static void timestamp_and_log(int pri, char *msg, int len)
{ {
char *timestamp; char *timestamp;
if (ENABLE_FEATURE_REMOTE_LOG && !(option_mask32 & OPT_locallog))
return;
if (len < 16 || msg[3] != ' ' || msg[6] != ' ' if (len < 16 || msg[3] != ' ' || msg[6] != ' '
|| msg[9] != ':' || msg[12] != ':' || msg[15] != ' ' || msg[9] != ':' || msg[12] != ':' || msg[15] != ' '
) { ) {
@ -400,18 +414,14 @@ static void timestamp_and_log(int pri, char *msg, int len)
timestamp[15] = '\0'; timestamp[15] = '\0';
/* Log message locally (to file or shared mem) */ /* Log message locally (to file or shared mem) */
if (!ENABLE_FEATURE_REMOTE_LOG || (option_mask32 & OPT_locallog)) { if (option_mask32 & OPT_small)
if (LOG_PRI(pri) < G.logLevel) { sprintf(G.printbuf, "%s %s\n", timestamp, msg);
if (option_mask32 & OPT_small) else {
sprintf(G.printbuf, "%s %s\n", timestamp, msg); char res[20];
else { parse_fac_prio_20(pri, res);
char res[20]; sprintf(G.printbuf, "%s %s %s %s\n", timestamp, G.localHostName, res, msg);
parse_fac_prio_20(pri, res);
sprintf(G.printbuf, "%s %s %s %s\n", timestamp, G.localHostName, res, msg);
}
log_locally(G.printbuf);
}
} }
log_locally(G.printbuf);
} }
static void split_escape_and_log(char *tmpbuf, int len) 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++ = c;
} }
*q = '\0'; *q = '\0';
/* Now log it */ /* 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; 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) ATTRIBUTE_NORETURN;
static void do_syslogd(void) static void do_syslogd(void)
{ {
@ -505,10 +535,7 @@ static void do_syslogd(void)
signal(SIGTERM, quit_signal); signal(SIGTERM, quit_signal);
signal(SIGQUIT, quit_signal); signal(SIGQUIT, quit_signal);
signal(SIGHUP, SIG_IGN); signal(SIGHUP, SIG_IGN);
signal(SIGCHLD, SIG_IGN); /* signal(SIGCHLD, SIG_IGN); - why? */
#ifdef SIGCLD
signal(SIGCLD, SIG_IGN);
#endif
#ifdef SYSLOGD_MARK #ifdef SYSLOGD_MARK
signal(SIGALRM, do_mark); signal(SIGALRM, do_mark);
alarm(G.markInterval); alarm(G.markInterval);
@ -554,19 +581,21 @@ static void do_syslogd(void)
#if ENABLE_FEATURE_REMOTE_LOG #if ENABLE_FEATURE_REMOTE_LOG
/* We are not modifying log messages in any way before send */ /* We are not modifying log messages in any way before send */
/* Remote site cannot trust _us_ anyway and need to do validation again */ /* Remote site cannot trust _us_ anyway and need to do validation again */
if (G.remoteAddr) { if (G.remoteAddrStr) {
if (-1 == G.remoteFD) { if (-1 == G.remoteFD) {
G.remoteFD = socket(G.remoteAddr->sa.sa_family, SOCK_DGRAM, 0); G.remoteFD = try_to_resolve_remote();
} if (-1 == G.remoteFD)
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);
} }
/* 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 #endif
split_escape_and_log(G.recvbuf, sz); if (!ENABLE_FEATURE_REMOTE_LOG || (option_mask32 & OPT_locallog))
} /* for */ split_escape_and_log(G.recvbuf, sz);
} /* for (;;) */
} }
int syslogd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; 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 OPTION_DECL;
char *p; 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 */ /* do normal option parsing */
opt_complementary = "=0"; /* no non-option params */ opt_complementary = "=0"; /* no non-option params */
@ -595,12 +627,6 @@ int syslogd_main(int argc, char **argv)
if (option_mask32 & OPT_rotatecnt) // -b if (option_mask32 & OPT_rotatecnt) // -b
G.logFileRotate = xatou_range(opt_b, 0, 99); G.logFileRotate = xatou_range(opt_b, 0, 99);
#endif #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 ENABLE_FEATURE_IPC_SYSLOG
if (opt_C) // -Cn if (opt_C) // -Cn
G.shm_size = xatoul_range(opt_C, 4, INT_MAX/1024) * 1024; G.shm_size = xatoul_range(opt_C, 4, INT_MAX/1024) * 1024;