refactor so I can track and ignore recent packets of any type

src/mesh/PacketHistory.cpp

@@ -0,0 +1,52 @@
+#include "PacketHistory.h"
+#include "configuration.h"
+
+/// We clear our old flood record five minute after we see the last of it
+#define FLOOD_EXPIRE_TIME (5 * 60 * 1000L)
+
+PacketHistory::PacketHistory()
+{
+    recentPackets.reserve(MAX_NUM_NODES); // Prealloc the worst case # of records - to prevent heap fragmentation
+                                          // setup our periodic task
+}
+
+/**
+ * Update recentBroadcasts and return true if we have already seen this packet
+ */
+bool PacketHistory::wasSeenRecently(const MeshPacket *p)
+{
+    if (p->id == 0) {
+        DEBUG_MSG("Ignoring message with zero id\n");
+        return false; // Not a floodable message ID, so we don't care
+    }
+
+    uint32_t now = millis();
+    for (size_t i = 0; i < recentPackets.size();) {
+        PacketRecord &r = recentPackets[i];
+
+        if ((now - r.rxTimeMsec) >= FLOOD_EXPIRE_TIME) {
+            // DEBUG_MSG("Deleting old broadcast record %d\n", i);
+            recentPackets.erase(recentPackets.begin() + i); // delete old record
+        } else {
+            if (r.id == p->id && r.sender == p->from) {
+                DEBUG_MSG("Found existing broadcast record for fr=0x%x,to=0x%x,id=%d\n", p->from, p->to, p->id);
+
+                // Update the time on this record to now
+                r.rxTimeMsec = now;
+                return true;
+            }
+
+            i++;
+        }
+    }
+
+    // Didn't find an existing record, make one
+    PacketRecord r;
+    r.id = p->id;
+    r.sender = p->from;
+    r.rxTimeMsec = now;
+    recentPackets.push_back(r);
+    DEBUG_MSG("Adding broadcast record for fr=0x%x,to=0x%x,id=%d\n", p->from, p->to, p->id);
+
+    return false;
+}