Improved sleep/alarm/mark implementation by

Alan Jenkins <alan-jenkins@tuffmail.co.uk>

diff --git a/syslogd.c b/syslogd.c
index 853e23a..dc350c9 100644 (file)
--- a/syslogd.c
+++ b/syslogd.c
@@ -783,6 +783,8 @@ int LogPort;                /* port number for INET connections */
 int    Initialized = 0;        /* set when we have initialized ourselves */
 int    MarkInterval = 20 * 60; /* interval between marks in seconds */
 int    MarkSeq = 0;            /* mark sequence number */
+int    LastAlarm = 0;          /* last value passed to alarm() (seconds)  */
+int    DupesPending = 0;       /* Number of unflushed duplicate messages */
 int    NoFork = 0;             /* don't fork - don't run in daemon mode */
 int    AcceptRemote = 0;       /* receive messages that come via UDP */
 char   **StripDomains = NULL;  /* these domains may be stripped before writing logs */
@@ -1054,7 +1056,9 @@ int main(argc, argv)
        (void) signal(SIGALRM, domark);
        (void) signal(SIGUSR1, Debug ? debug_switch : SIG_IGN);
        (void) signal(SIGXFSZ, SIG_IGN);
-       (void) alarm(TIMERINTVL);
+
+       LastAlarm = MarkInterval;
+       alarm(LastAlarm);
 
        /* Create a partial message table for all file descriptors. */
        num_fds = getdtablesize();
@@ -1698,6 +1702,17 @@ void logmsg(pri, msg, from, flags)
                        dprintf("msg repeated %d times, %ld sec of %d.\n",
                            f->f_prevcount, now - f->f_time,
                            repeatinterval[f->f_repeatcount]);
+
+                       if (f->f_prevcount == 1 && DupesPending++ == 0) {
+                               dprintf("setting alarm to flush duplicate messages\n");
+
+                               LastAlarm -= alarm(0);
+                               MarkSeq += LastAlarm;
+                               if (LastAlarm > TIMERINTVL)
+                                       LastAlarm = TIMERINTVL;
+                               alarm(LastAlarm);
+                       }
+
                        /*
                         * If domark would have logged this by now,
                         * flush it now (so we don't hold isolated messages),
@@ -1710,8 +1725,17 @@ void logmsg(pri, msg, from, flags)
                        }
                } else {
                        /* new line, save it */
-                       if (f->f_prevcount)
+                       if (f->f_prevcount) {
                                fprintlog(f, (char *)from, 0, (char *)NULL);
+
+                               if (--DupesPending == 0) {
+                                       dprintf("unsetting duplicate message flush alarm\n");
+
+                                       MarkSeq += LastAlarm - alarm(0);
+                                       LastAlarm = MarkInterval - MarkSeq;
+                                       alarm(LastAlarm);
+                               }
+                       }
                        f->f_prevpri = pri;
                        f->f_repeatcount = 0;
                        (void) strncpy(f->f_lasttime, timestamp, 15);
@@ -2164,10 +2188,10 @@ void domark()
 
        if (MarkInterval > 0) {
                now = time(0);
-               MarkSeq += TIMERINTVL;
+               MarkSeq += LastAlarm;
                if (MarkSeq >= MarkInterval) {
                        logmsg(LOG_MARK|LOG_INFO, "-- MARK --", LocalHostName, ADDDATE|MARK);
-                       MarkSeq = 0;
+                       MarkSeq -= MarkInterval;
                }
 
 #ifdef SYSV
@@ -2182,11 +2206,17 @@ void domark()
                                    repeatinterval[f->f_repeatcount]);
                                fprintlog(f, LocalHostName, 0, (char *)NULL);
                                BACKOFF(f);
+                               DupesPending--;
                        }
                }
        }
        (void) signal(SIGALRM, domark);
-       (void) alarm(TIMERINTVL);
+
+       LastAlarm = MarkInterval - MarkSeq;
+       if (DupesPending && LastAlarm > TIMERINTVL)
+               LastAlarm = TIMERINTVL;
+
+       (void) alarm(LastAlarm);
 }
 
 void debug_switch()