refactor replay: add some overrideable methods

src/modules/replay/replay.hpp

@@ -59,7 +59,7 @@ public:
 	Replay();
 
 	/// Destructor, also waits for task exit
-	~Replay();
+	virtual ~Replay();
 
 	/**
 	 * Start task.
@@ -82,15 +82,8 @@ public:
 	static void setupReplayFile(const char *file_name);
 
 	static bool isSetup() { return _replay_file; }
-private:
-	bool _task_should_exit = false;
-	std::set<std::string> _overridden_params;
-	std::map<std::string, std::string> _file_formats; ///< all formats we read from the file
 
-	uint64_t _file_start_time;
-	uint64_t _replay_start_time;
-	std::streampos _data_section_start; ///< first ADD_LOGGED_MSG message
-	std::vector<uint8_t> _read_buffer;
+protected:
 
 	struct Subscription {
 
@@ -102,6 +95,48 @@ private:
 		std::streampos next_read_pos;
 		uint64_t next_timestamp; ///< timestamp of the file
 	};
+
+	/**
+	 * publish an orb topic
+	 * @param sub
+	 * @param data
+	 * @return true if published, false otherwise
+	 */
+	bool publishTopic(Subscription &sub, void *data);
+
+	/**
+	 * called when entering the main replay loop
+	 */
+	virtual void onEnterMainLoop() {};
+	/**
+	 * called when exiting the main replay loop
+	 */
+	virtual void onExitMainLoop() {};
+
+	/**
+	 * handle delay until topic can be published.
+	 * @param next_file_timestamp timestamp of next message to publish
+	 * @param timestamp_offset offset between file start time and replay start time
+	 * @return timestamp that the message to publish should have
+	 */
+	virtual uint64_t handleTopicDelay(uint64_t next_file_time, uint64_t timestamp_offset);
+
+	/**
+	 * handle the publication of a topic update
+	 * @return true if published, false otherwise
+	 */
+	virtual bool handleTopicUpdate(Subscription &sub, void *data);
+
+private:
+	bool _task_should_exit = false;
+	std::set<std::string> _overridden_params;
+	std::map<std::string, std::string> _file_formats; ///< all formats we read from the file
+
+	uint64_t _file_start_time;
+	uint64_t _replay_start_time;
+	std::streampos _data_section_start; ///< first ADD_LOGGED_MSG message
+	std::vector<uint8_t> _read_buffer;
+
 	std::vector<Subscription> _subscriptions;
 
 	/** keep track of file position to avoid adding a subscription multiple times. */

src/modules/replay/replay_main.cpp

@@ -627,6 +627,8 @@ void Replay::task_main()
 		return;
 	}
 
+	onEnterMainLoop();
+
 	_replay_start_time = hrt_absolute_time();
 
 	PX4_INFO("Replay in progress...");
@@ -687,13 +689,8 @@ void Replay::task_main()
 		last_additional_message_pos = next_additional_message_pos;
 
 
-		//wait if necessary
-		const uint64_t publish_timestamp = next_file_time + timestamp_offset;
-		uint64_t cur_time = hrt_absolute_time();
-		// if some topics have a timestamp smaller than the log file start, publish them immediately
-		if (cur_time < publish_timestamp && next_file_time > _file_start_time) {
-			usleep(publish_timestamp - cur_time);
-		}
+		const uint64_t publish_timestamp = handleTopicDelay(next_file_time, timestamp_offset);
+
 
 		//It's time to publish
 		const size_t msg_read_size = sub.orb_meta->o_size_no_padding;
@@ -703,11 +700,10 @@ void Replay::task_main()
 		replay_file.read((char *)_read_buffer.data(), msg_read_size);
 		*(uint64_t *)(_read_buffer.data() + sub.timestamp_offset) = publish_timestamp;
 
-		if (publishTopic(sub, _read_buffer.data())) {
+		if (handleTopicUpdate(sub, _read_buffer.data())) {
 			++nr_published_messages;
 		}
 
-
 		nextDataMessage(replay_file, _subscriptions[next_msg_id], next_msg_id);
 
 		//TODO: output status (eg. every sec), including total duration...
@@ -726,6 +722,29 @@ void Replay::task_main()
 
 		//TODO: should we close the log file & exit (optionally, by adding a parameter -q) ?
 	}
+
+	onExitMainLoop();
+}
+
+bool Replay::handleTopicUpdate(Subscription &sub, void *data)
+{
+	return publishTopic(sub, data);
+}
+
+uint64_t Replay::handleTopicDelay(uint64_t next_file_time, uint64_t timestamp_offset)
+{
+
+	const uint64_t publish_timestamp = next_file_time + timestamp_offset;
+
+	//wait if necessary
+	uint64_t cur_time = hrt_absolute_time();
+
+	// if some topics have a timestamp smaller than the log file start, publish them immediately
+	if (cur_time < publish_timestamp && next_file_time > _file_start_time) {
+		usleep(publish_timestamp - cur_time);
+	}
+
+	return publish_timestamp;
 }
 
 bool Replay::publishTopic(Subscription &sub, void *data)
@@ -875,7 +894,7 @@ int replay_main(int argc, char *argv[])
 			return 1;
 		}
 
-		if (PX4_OK != replay::instance->start(quiet, apply_params_only)) {
+		if (PX4_OK != Replay::start(quiet, apply_params_only)) {
 			PX4_ERR("start failed");
 			return 1;
 		}