Fix to ignore 0 or less readlengths after the first one

bk: 4226160dXQxAS6kWBdf5U-pZBLdsGA

diff --git a/ntpd/ntp_io.c b/ntpd/ntp_io.c
index 08b522a426d817b02602d826a034b6f8c42a0010..2614657761e09c757e388c3e5a98fbfca3d8e01c 100644 (file)
--- a/ntpd/ntp_io.c
+++ b/ntpd/ntp_io.c
@@ -1829,6 +1829,15 @@ input_handler(
        )
 {
 
+       /*
+        * List of fd's to skip the read
+        * We don't really expect to have this many
+        * refclocks on a system
+        */
+#define MAXSKIPS  20
+       int skiplist[MAXSKIPS];
+       int totskips;
+       isc_boolean_t skip;
        int nonzeroreads;
        int buflen;
        register int i, n;
@@ -1843,6 +1852,15 @@ input_handler(
        int select_count = 0;
        static int handler_count = 0;
 
+       /*
+        * Initialize the skip list
+        */
+       for (i = 0; i<MAXSKIPS; i++)
+       {
+               skiplist[i] = 0;
+       }
+       totskips = 0;
+
        ++handler_count;
        if (handler_count != 1)
            msyslog(LOG_ERR, "input_handler: handler_count is %d!", handler_count);
@@ -1861,6 +1879,11 @@ input_handler(
        fds = activefds;
        tvzero.tv_sec = tvzero.tv_usec = 0;
 
+#ifdef REFCLOCK
+       /*
+        * Check out the reference clocks first, if any
+        */
+
        nonzeroreads = 1;
        while (nonzeroreads > 0)
        {
@@ -1869,10 +1892,6 @@ input_handler(
                ++select_count;
                ++handler_pkts;
 
-#ifdef REFCLOCK
-       /*
-        * Check out the reference clocks first, if any
-        */
                if (refio != 0)
                {
                        register struct refclockio *rp;
@@ -1880,6 +1899,20 @@ input_handler(
                        for (rp = refio; rp != 0; rp = rp->next)
                        {
                                fd = rp->fd;
+                               skip = ISC_FALSE;
+                               /* Check for skips */
+                               for (i = 0; i < totskips; i++)
+                               {
+                                       if (fd == skiplist[i])
+                                       {
+                                               skip = ISC_TRUE;
+                                               break;
+                                       }
+                               }
+                               /* fd was on skip list */
+                               if (skip == ISC_TRUE)
+                                       continue;
+
                                if (FD_ISSET(fd, &fds))
                                {
                                        n--;
@@ -1891,6 +1924,11 @@ input_handler(
                                                packets_dropped++;
                                                if (buflen > 0)
                                                        nonzeroreads++;
+                                               else
+                                               {
+                                                       skiplist[totskips] = fd;
+                                                       totskips++;
+                                               }
                                                continue;       /* Keep reading until drained */
                                        }
 
@@ -1908,11 +1946,17 @@ input_handler(
                                                        netsyslog(LOG_ERR, "clock read fd %d: %m", fd);
                                                }
                                                freerecvbuf(rb);
-                                               break;
+                                               skiplist[totskips] = fd;
+                                               totskips++;
+                                               continue;
                                        }
                                        if(buflen > 0)
                                                nonzeroreads++;
-
+                                       else
+                                       {
+                                               skiplist[totskips] = fd;
+                                               totskips++;
+                                       }
                                        /*
                                         * Got one.  Mark how and when it got here,
                                         * put it on the full list and do