Replay: print message when gap perceived in log

Tools/Replay/LR_MsgHandler.cpp

@@ -445,6 +445,14 @@ void LR_MsgHandler_PARM::process_message(uint8_t *msg)
     }
 }
 
+void LR_MsgHandler_PM::process_message(uint8_t *msg)
+{
+    uint32_t new_logdrop;
+    if (field_value(msg, "LogDrop", new_logdrop) &&
+        new_logdrop != 0) {
+        printf("PM.LogDrop: %u dropped at timestamp %lu\n", new_logdrop, last_timestamp_usec);
+    }
+}
 
 void LR_MsgHandler_SIM::process_message(uint8_t *msg)
 {

Tools/Replay/LR_MsgHandler.h

@@ -435,6 +435,18 @@ public:
     virtual void process_message(uint8_t *msg);
 };
 
+class LR_MsgHandler_PM : public LR_MsgHandler
+{
+public:
+    LR_MsgHandler_PM(log_Format &_f, DataFlash_Class &_dataflash,
+                     uint64_t &_last_timestamp_usec)
+        : LR_MsgHandler(_f, _dataflash, _last_timestamp_usec) { };
+
+    virtual void process_message(uint8_t *msg);
+
+private:
+
+};
 
 class LR_MsgHandler_SIM : public LR_MsgHandler
 {

Tools/Replay/LogReader.cpp

@@ -266,6 +266,9 @@ bool LogReader::handle_log_format_msg(const struct log_Format &f)
 	  msgparser[f.type] = new LR_MsgHandler_CHEK(formats[f.type], dataflash,
                                                      last_timestamp_usec,
                                                      check_state);
+	} else if (streq(name, "PM")) {
+	  msgparser[f.type] = new LR_MsgHandler_PM(formats[f.type], dataflash,
+                                                   last_timestamp_usec);
 	} else {
             debug("  No parser for (%s)\n", name);
 	}

Tools/Replay/Replay.cpp

@@ -765,6 +765,7 @@ void Replay::log_check_solution(void)
 
 void Replay::loop()
 {
+    uint64_t last_timestamp = 0;
     while (true) {
         char type[5];
 
@@ -780,6 +781,16 @@ void Replay::loop()
             fclose(plotf);
             break;
         }
+
+        if (last_timestamp != 0) {
+            uint64_t gap = AP_HAL::micros64() - last_timestamp;
+            if (gap > 40000) {
+                ::printf("Gap in log at timestamp=%lu of length %luus\n",
+                         last_timestamp, gap);
+            }
+        }
+        last_timestamp = AP_HAL::micros64();
+
         read_sensors(type);
 
         if (streq(type,"ATT")) {