use std::list to cache outpackets from sniffer

Author: habazut

Sniffer.cpp

@@ -192,9 +192,10 @@ void IRAM_ATTR Sniffer::processInterrupt(int32_t capticks, bool posedge) {
 	      packeterror(); // or better?
 	    }
 	    DCCPacket temppacket(dccbytes, dcclen);
-	    if (true) { //if (!(temppacket == outpacket)) {
-	      // we have something new to fetch
-	      outpacket = temppacket;
+	    if (!(temppacket == prevpacket)) {
+	      // we have something new to offer to the fetch routine
+	      outpacket.push_back(temppacket);
+	      prevpacket = temppacket;
 	      fetchflag = true;
 	    }
 	    return;

Sniffer.h

@@ -18,6 +18,7 @@
  */
 #ifdef ARDUINO_ARCH_ESP32
 #include <Arduino.h>
+#include <list>
 #include "driver/mcpwm.h"
 #include "soc/mcpwm_struct.h"
 #include "soc/mcpwm_reg.h"
@@ -46,8 +47,11 @@ class Sniffer {
     // packet with length 0 (which is no packet)
     DCCPacket p;
     noInterrupts();
+    if (!outpacket.empty()) {
+      p = outpacket.front();
+      outpacket.pop_front();
+    }
     if (fetchflag) {
-      p = outpacket;
       fetchflag = false; // (data has been fetched)
     }
     interrupts();
@@ -67,6 +71,7 @@ class Sniffer {
   // these vars are used as interface to other parts of sniffer
   byte halfbitcounter = 0;
   bool fetchflag = false;
-  DCCPacket outpacket;
+  std::list<DCCPacket> outpacket;
+  DCCPacket prevpacket;
 };
 #endif