journald: log when we fail to forward messages to syslog

[elogind.git] / src / journal / journald-syslog.c

diff --git a/src/journal/journald-syslog.c b/src/journal/journald-syslog.c
index 9db9198a49a082829e25e74ade9e1b6ecf579c0e..d3e0f6f6c11868e4dcf5a9bd8c88f4d063a170c0 100644 (file)
--- a/src/journal/journald-syslog.c
+++ b/src/journal/journald-syslog.c
@@ -23,12 +23,16 @@
 #include <stddef.h>
 #include <sys/epoll.h>
 
 #include <stddef.h>
 #include <sys/epoll.h>
 

+#include "systemd/sd-messages.h"

 #include "socket-util.h"
 #include "journald.h"
 #include "journald-syslog.h"
 #include "journald-kmsg.h"
 #include "journald-console.h"
 
 #include "socket-util.h"
 #include "journald.h"
 #include "journald-syslog.h"
 #include "journald-kmsg.h"
 #include "journald-console.h"
 

+/* Warn once every 30s if we missed syslog message */
+#define WARN_FORWARD_SYSLOG_MISSED_USEC (30 * USEC_PER_SEC)
+

 static void forward_syslog_iovec(Server *s, const struct iovec *iovec, unsigned n_iovec, struct ucred *ucred, struct timeval *tv) {
         struct msghdr msghdr;
         struct cmsghdr *cmsg;
 static void forward_syslog_iovec(Server *s, const struct iovec *iovec, unsigned n_iovec, struct ucred *ucred, struct timeval *tv) {
         struct msghdr msghdr;
         struct cmsghdr *cmsg;


@@ -74,8 +78,10 @@ static void forward_syslog_iovec(Server *s, const struct iovec *iovec, unsigned
 
         /* The socket is full? I guess the syslog implementation is
          * too slow, and we shouldn't wait for that... */
 
         /* The socket is full? I guess the syslog implementation is
          * too slow, and we shouldn't wait for that... */

-        if (errno == EAGAIN)
+        if (errno == EAGAIN) {
+                s->n_forward_syslog_missed++;

                 return;
                 return;

+        }

 
         if (ucred && errno == ESRCH) {
                 struct ucred u;
 
         if (ucred && errno == ESRCH) {
                 struct ucred u;


@@ -91,8 +97,10 @@ static void forward_syslog_iovec(Server *s, const struct iovec *iovec, unsigned
                 if (sendmsg(s->syslog_fd, &msghdr, MSG_NOSIGNAL) >= 0)
                         return;
 
                 if (sendmsg(s->syslog_fd, &msghdr, MSG_NOSIGNAL) >= 0)
                         return;
 

-                if (errno == EAGAIN)
+                if (errno == EAGAIN) {
+                        s->n_forward_syslog_missed++;

                         return;
                         return;

+                }

         }
 
         if (errno != ENOENT)
         }
 
         if (errno != ENOENT)


@@ -464,3 +472,20 @@ int server_open_syslog_socket(Server *s) {
 
         return 0;
 }
 
         return 0;
 }

+
+void server_maybe_warn_forward_syslog_missed(Server *s) {
+        usec_t n;
+        assert(s);
+
+        if (s->n_forward_syslog_missed <= 0)
+                return;
+
+        n = now(CLOCK_MONOTONIC);
+        if (s->last_warn_forward_syslog_missed + WARN_FORWARD_SYSLOG_MISSED_USEC > n)
+                return;
+
+        server_driver_message(s, SD_MESSAGE_FORWARD_SYSLOG_MISSED, "Forwarding to syslog missed %u messages.", s->n_forward_syslog_missed);
+
+        s->n_forward_syslog_missed = 0;
+        s->last_warn_forward_syslog_missed = n;
+}