- applied a patch from mildew to prevent rsyslogd from freezing under heavy

    load. This could happen when the queue was full. Now, we drop messages
    but rsyslogd remains active.

3 files changed, 21 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 3379f0e6..2c666580 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -22,6 +22,9 @@ Version 1.17.6 (rgerhards), 2007-07-3?
 - fixed an invalid value for the MARK timer - unfortunately, there was
   a testing aid left in place. This resulted in quite frequent MARK messages
 - added $include config directive
+- applied a patch from mildew to prevent rsyslogd from freezing under heavy
+  load. This could happen when the queue was full. Now, we drop messages
+  but rsyslogd remains active.
 ---------------------------------------------------------------------------
 Version 1.17.5 (rgerhards), 2007-07-30
 - continued to work on output module modularization
diff --git a/configure.ac b/configure.ac
index 24e01f06..1e11c930 100644
--- a/configure.ac
+++ b/configure.ac
@@ -28,6 +28,7 @@ case "${host}" in
 esac
 
 # Checks for libraries.
+AC_CHECK_LIB(rt,clock_gettime,,,)
 
 # Checks for header files.
 AC_HEADER_RESOLV
diff --git a/syslogd.c b/syslogd.c
index 25e49448..7f0a4673 100644
--- a/syslogd.c
+++ b/syslogd.c
@@ -163,6 +163,9 @@
 #include <sys/file.h>
 #include <sys/un.h>
 #include <sys/time.h>
+#ifdef BSD
+# include <sys/timespec.h>
+#endif
 #include <sys/resource.h>
 #include <signal.h>
 
@@ -2510,6 +2513,7 @@ static void *singleWorker()
 		} else { /* the mutex must be unlocked in any case (important for termination) */
 			pthread_mutex_unlock(fifo->mut);
 		}
+		
 		if(debugging_on && bGlblDone && !fifo->empty)
 			dprintf("Worker does not yet terminate because it still has messages to process.\n");
 	}
@@ -2536,6 +2540,7 @@ static void enqueueMsg(msg_t *pMsg)
 {
 	int iRet;
 	msgQueue *fifo = pMsgQueue;
+	struct timespec t;
 
 	assert(pMsg != NULL);
 
@@ -2547,12 +2552,22 @@ static void enqueueMsg(msg_t *pMsg)
 		 processMsg(pMsg);
 	} else {
 		/* "normal" mode, threading initialized */
-		iRet = pthread_mutex_lock(fifo->mut);
+		pthread_mutex_lock(fifo->mut);
+			
 		while (fifo->full) {
 			dprintf ("enqueueMsg: queue FULL.\n");
-			pthread_cond_wait (fifo->notFull, fifo->mut);
+			
+			clock_gettime (CLOCK_REALTIME, &t);
+			t.tv_sec += 2;
+			
+			if(pthread_cond_timedwait (fifo->notFull,
+						   fifo->mut, &t) != 0) {
+				dprintf("enqueueMsg: cond timeout, dropping message!\n");
+				goto unlock;
+			}
 		}
 		queueAdd(fifo, MsgAddRef(pMsg));
+	unlock:
 		/* now activate the worker thread */
 		pthread_mutex_unlock(fifo->mut);
 		iRet = pthread_cond_signal(fifo->notEmpty);