Only display statistics in oping if packets have been received.

Also, don't devide by zero.

diff --git a/src/oping.c b/src/oping.c
index 485859d..5f0940d 100644 (file)
--- a/src/oping.c
+++ b/src/oping.c
@@ -182,7 +182,7 @@ void print_host (pingobj_iter_t *iter)
                if ((context->latency_min < 0.0) || (context->latency_min > latency))
                        context->latency_min = latency;
 
-               printf ("echo reply from %s (%s): icmp_seq=%u time=%.1f ms\n",
+               printf ("echo reply from %s (%s): icmp_seq=%u time=%.2f ms\n",
                                context->host, context->addr,
                                (unsigned int) sequence, latency);
        }
@@ -382,25 +382,32 @@ int main (int argc, char **argv)
                        iter = ping_iterator_next (iter))
        {
                ping_context_t *context;
-               double average;
-               double deviation;
 
                context = ping_iterator_get_context (iter);
 
-               average = context->latency_total / ((double) context->req_rcvd);
-               deviation = context->latency_total_square / ((double) context->req_rcvd);
-               deviation = sqrt (deviation - (average * average));
-
                printf ("\n--- %s ping statistics ---\n"
-                               "%i packets transmitted, %i received, %.2f%% packet loss, time %.1fms\n"
-                               "rtt min/avg/max/mdev = %.3f/%.3f/%.3f/%.3f ms\n",
+                               "%i packets transmitted, %i received, %.2f%% packet loss, time %.1fms\n",
                                context->host, context->req_sent, context->req_rcvd,
                                100.0 * (context->req_sent - context->req_rcvd) / ((double) context->req_sent),
-                               context->latency_total,
-                               context->latency_min,
-                               average,
-                               context->latency_max,
-                               deviation);
+                               context->latency_total);
+
+               if (context->req_rcvd != 0)
+               {
+                       double num_total;
+                       double average;
+                       double deviation;
+
+                       num_total = (double) context->req_rcvd;
+
+                       average = context->latency_total / num_total;
+                       deviation = sqrt ((context->latency_total_square / num_total) - (average * average));
+
+                       printf ("rtt min/avg/max/sdev = %.3f/%.3f/%.3f/%.3f ms\n",
+                                       context->latency_min,
+                                       average,
+                                       context->latency_max,
+                                       deviation);
+               }
 
                ping_iterator_set_context (iter, NULL);
                free (context);