Add log message for EOF in PlaybackFileBoard. (#663)

* Add log message for EOF in PlaybackFileBoard.

src/board_controller/playback_file_board.cpp

@@ -213,6 +213,7 @@ void PlaybackFileBoard::read_thread (int preset, std::string file)
     int timestamp_channel = board_preset["timestamp_channel"];
     double accumulated_time_delta = 0.0;
 
+    bool reached_end = false;
     while (keep_alive)
     {
         auto start = std::chrono::high_resolution_clock::now ();
@@ -245,6 +246,15 @@ void PlaybackFileBoard::read_thread (int preset, std::string file)
         }
         if ((!loopback) && (res == NULL))
         {
+            if (!reached_end)
+            {
+                reached_end = true;
+                // Log just once to inform the user that we have reached the endof the file, as we
+                // stop sending any samples. The user-programmer could be waiting as the stream
+                // needs to be stopped manually.
+                safe_logger (
+                    spdlog::level::trace, "End of file reached and not set to loop. Sleeping.");
+            }
 // busy wait instead exit
 #ifdef _WIN32
             Sleep (1);
@@ -400,4 +410,4 @@ int PlaybackFileBoard::get_file_offsets (std::string filename, std::vector<long
     }
 
     return (int)BrainFlowExitCodes::STATUS_OK;
-}
+}