print lost pings in loop and count mode, fixes #175

CHANGELOG.md

@@ -1,13 +1,30 @@
 fping 5.0 (unreleased)
 ======================
 
+## Incompatible Changes
+
+- In non-quiet loop and count mode, a line is printed for every lost packet
+  (#175, thanks @kbucheli):
+
+  ```
+  $ fping -D -c2 8.8.8.8 8.8.8.7
+  [1596092373.18423] 8.8.8.8 : [0], 84 bytes, 12.8 ms (12.8 avg, 0% loss)
+  [1596092374.18223] 8.8.8.7 : [0], timed out (NaN avg, 100% loss)
+  [1596092374.18424] 8.8.8.8 : [1], 84 bytes, 12.3 ms (12.5 avg, 0% loss)
+  [1596092375.18344] 8.8.8.7 : [1], timed out (NaN avg, 100% loss)
+
+  8.8.8.8 : xmt/rcv/%loss = 2/2/0%, min/avg/max = 12.3/12.5/12.8
+  8.8.8.7 : xmt/rcv/%loss = 2/0/100%
+  ```
+
 ## New features
 
-- Refactored event loop, now allowing for period (-p) to be smaller than
-  timeout (-t). The number of sent pings is now only incremented when the
-  response is received or when the timeout happens, so that the loss statistic
-  is always correct (especially important when using interval statistics (-Q)
-  (#193).
+- The number of sent pings is only counted when the pings are received or have
+  timed out, ensuring that the loss ratio will be always correct. This makes it
+  possible, for example, to use loop mode (-l) with interval statistics (-Q)
+  and a timeout larger than period, without having the issue that initially
+  some pings would be reported as missing (#193)
+
 - Improved precision of measurements from 10us to 1us (#136, thanks @tycho)
 
 

ci/test-08-options-n-q.pl

@@ -31,7 +31,12 @@ $cmd->stderr_is_eq("fping: use either one of -d or -n\n");
 {
 my $cmd = Test::Command->new(cmd => "fping -t100 -p 100 -o -c 5 8.8.8.7");
 $cmd->exit_is_num(1);
-$cmd->stdout_is_eq("");
+$cmd->stdout_is_eq("8.8.8.7 : [0], timed out (NaN avg, 100% loss)
+8.8.8.7 : [1], timed out (NaN avg, 100% loss)
+8.8.8.7 : [2], timed out (NaN avg, 100% loss)
+8.8.8.7 : [3], timed out (NaN avg, 100% loss)
+8.8.8.7 : [4], timed out (NaN avg, 100% loss)
+");
 $cmd->stderr_like(qr{^\s*8\.8\.8\.7 : xmt/rcv/%loss = 5/0/100%, outage\(ms\) = 50\d\s*$});
 }
 

src/fping.c

@@ -1262,6 +1262,29 @@ void main_loop()
 
             stats_add(h, event->ping_index, 0, -1);
 
+            if (per_recv_flag) {
+                if (timestamp_flag) {
+                    printf("[%10.5f] ", (double)current_time_ns / 1e9);
+                }
+                printf("%-*s : [%d], timed out",
+                    max_hostname_len, h->host, event->ping_index);
+                if(h->num_recv > 0) {
+                    printf(" (%s avg, ", sprint_tm(h->total_time / h->num_recv));
+                }
+                else {
+                    printf(" (NaN avg, ");
+                }
+                if (h->num_recv <= h->num_sent) {
+                    printf("%d%% loss)",
+                        ((h->num_sent - h->num_recv) * 100) / h->num_sent);
+                }
+                else {
+                    printf("%d%% return)",
+                        (h->num_recv_total * 100) / h->num_sent);
+                }
+                printf("\n");
+            }
+
             /* do we need to send a retry? */
             if (!loop_flag && !count_flag) {
                 if (h->num_sent < retry + 1) {
@@ -2348,7 +2371,7 @@ int wait_for_reply(int64_t wait_time)
     /* print received ping (unless --quiet) */
     if (per_recv_flag) {
         if (timestamp_flag) {
-            printf("[%10.5f] ", (double)(recv_time / 1000000)/1000);
+            printf("[%10.5f] ", (double)recv_time / 1e9);
         }
         avg = h->total_time / h->num_recv;
         printf("%-*s : [%d], %d bytes, %s ms",