Add free() function to memory pool to get number of free chunks.

TNC/HdlcFrame.cpp

@@ -3,6 +3,7 @@
 
 #include "HdlcFrame.hpp"
 #include "Log.h"
+#include "main.h"
 #include "cmsis_os.h"
 
 namespace mobilinkd { namespace tnc { namespace hdlc {

TNC/HdlcFrame.hpp

@@ -37,7 +37,7 @@ public:
         DATA = 0, TX_DELAY, P_PERSIST, SLOT_TIME, TX_TAIL, DUPLEX, HARDWARE,
         TEXT, LOG};
 
-    enum Source { RF_DATA = 0x80 };
+    enum Source { RF_DATA = 0x80, BERT = 0x30, STREAM = 0x20, PACKET = 0x10 };
 
 private:
     data_type data_;

TNC/memory.hpp

@@ -65,6 +65,8 @@ struct Pool {
         free_list.push_back(*item);
         taskEXIT_CRITICAL_FROM_ISR(x);
     }
+
+    size_t free() const { return free_list.size(); }
 };