From 6a113878616269d4c0db96139006203c9e1946a2 Mon Sep 17 00:00:00 2001
From: Oliver Jowett <oliver.jowett@flightaware.com>
Date: Thu, 4 Feb 2021 16:33:26 +0800
Subject: [PATCH] Collect stats on messages received by DF type

---
 mode_s.c |  3 +++
 net_io.c | 12 ++++++++++--
 stats.c  |  9 ++++++++-
 stats.h  |  2 ++
 4 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/mode_s.c b/mode_s.c
index 5cd9612..f2e7095 100644
--- a/mode_s.c
+++ b/mode_s.c
@@ -2142,6 +2142,9 @@ void useModesMessage(struct modesMessage *mm) {
     struct aircraft *a;
 
     ++Modes.stats_current.messages_total;
+    if (mm->msgtype >= 0 && mm->msgtype < 32) {
+        ++Modes.stats_current.messages_by_df[mm->msgtype];
+    }
 
     // Track aircraft state
     a = trackUpdateFromMessage(mm);
diff --git a/net_io.c b/net_io.c
index 7636087..d482998 100644
--- a/net_io.c
+++ b/net_io.c
@@ -1791,7 +1791,7 @@ static char * appendStatsJson(char *p,
                            ",\"tracks\":{\"all\":%u"
                            ",\"single_message\":%u"
                            ",\"unreliable\":%u}"
-                           ",\"messages\":%u}",
+                           ",\"messages\":%u",
                            st->cpr_surface,
                            st->cpr_airborne,
                            st->cpr_global_ok,
@@ -1813,7 +1813,15 @@ static char * appendStatsJson(char *p,
                            st->unique_aircraft,
                            st->single_message_aircraft,
                            st->unreliable_aircraft,
-                           st->messages_total);
+                          st->messages_total);
+
+        for (i = 0; i < 32; ++i) {
+            if (i == 0)
+                p = safe_snprintf(p, end, ",\"messages_by_df\":[%u", st->messages_by_df[i]);
+            else
+                p = safe_snprintf(p, end, ",%u", st->messages_by_df[i]);
+        }
+        p = safe_snprintf(p, end, "]}");
     }
 
     return p;
diff --git a/stats.c b/stats.c
index 3cfaa94..d433746 100644
--- a/stats.c
+++ b/stats.c
@@ -125,9 +125,14 @@ void display_stats(struct stats *st) {
             printf("    %8u accepted with %d-bit error repaired\n", st->remote_accepted[j], j);
     }
 
-    printf("%u total usable messages\n",
+    printf("%8u total usable messages\n",
            st->messages_total);
 
+    for (unsigned i = 0; i < 32; ++i) {
+        if (st->messages_by_df[i])
+            printf("  %8u DF%u messages\n", st->messages_by_df[i], i);
+    }
+
     printf("%8u surface position messages received\n"
            "%8u airborne position messages received\n"
            "%8u global CPR attempts with valid positions\n"
@@ -310,6 +315,8 @@ void add_stats(const struct stats *st1, const struct stats *st2, struct stats *t
 
     // total messages:
     target->messages_total = st1->messages_total + st2->messages_total;
+    for (i = 0; i < 32; ++i)
+        target->messages_by_df[i] = st1->messages_by_df[i] + st2->messages_by_df[i];
 
     // CPR decoding:
     target->cpr_surface = st1->cpr_surface + st2->cpr_surface;
diff --git a/stats.h b/stats.h
index bd06bb0..1935b12 100644
--- a/stats.h
+++ b/stats.h
@@ -94,6 +94,8 @@ struct stats {
 
     // total messages:
     uint32_t messages_total;
+    // .. divided by DF
+    uint32_t messages_by_df[32];
 
     // CPR decoding:
     unsigned int cpr_surface;