mavlink: bring class LogListHelper into MavlinkLogHandler (#14452)

This is in order to avoid dynamic allocation of LogListHelper when downloading logs.

src/modules/mavlink/mavlink_log_handler.h

@@ -1,6 +1,6 @@
 /****************************************************************************
  *
- *   Copyright (c) 2014, 2015 PX4 Development Team. All rights reserved.
+ *   Copyright (c) 2014, 2020 PX4 Development Team. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -46,52 +46,12 @@
 
 class Mavlink;
 
-// Log Listing Helper
-class LogListHelper
-{
-public:
-	LogListHelper();
-	~LogListHelper();
-
-public:
-	static void delete_all(const char *dir);
-
-public:
-
-	bool        get_entry(int idx, uint32_t &size, uint32_t &date, char *filename = 0, int filename_len = 0);
-	bool        open_for_transmit();
-	size_t      get_log_data(uint8_t len, uint8_t *buffer);
-
-	enum {
-		LOG_HANDLER_IDLE,
-		LOG_HANDLER_LISTING,
-		LOG_HANDLER_SENDING_DATA
-	};
-
-	int         next_entry;
-	int         last_entry;
-	int         log_count;
-
-	int         current_status;
-	uint16_t    current_log_index;
-	uint32_t    current_log_size;
-	uint32_t    current_log_data_offset;
-	uint32_t    current_log_data_remaining;
-	FILE       *current_log_filep;
-	char        current_log_filename[128];
-
-private:
-	void        _init();
-	bool        _get_session_date(const char *path, const char *dir, time_t &date);
-	void        _scan_logs(FILE *f, const char *dir, time_t &date);
-	bool        _get_log_time_size(const char *path, const char *file, time_t &date, uint32_t &size);
-};
-
 // MAVLink LOG_* Message Handler
 class MavlinkLogHandler
 {
 public:
 	MavlinkLogHandler(Mavlink *mavlink);
+	~MavlinkLogHandler();
 
 	// Handle possible LOG message
 	void handle_message(const mavlink_message_t *msg);
@@ -105,15 +65,43 @@ public:
 	unsigned get_size();
 
 private:
+	enum class LogHandlerState {
+		Inactive,     //There is no active action of log handler
+		Idle,         //The log handler is not sending list/data, but list has been sent
+		Listing,      //File list is being send
+		SendingData  //File Data is being send
+	};
 	void _log_message(const mavlink_message_t *msg);
 	void _log_request_list(const mavlink_message_t *msg);
 	void _log_request_data(const mavlink_message_t *msg);
 	void _log_request_erase(const mavlink_message_t *msg);
 	void _log_request_end(const mavlink_message_t *msg);
 
+	void _reset_list_helper();
+	void _init_list_helper();
+	bool _get_session_date(const char *path, const char *dir, time_t &date);
+	void _scan_logs(FILE *f, const char *dir, time_t &date);
+	bool _get_log_time_size(const char *path, const char *file, time_t &date, uint32_t &size);
+	static void _delete_all(const char *dir);
+	bool _get_entry(int idx, uint32_t &size, uint32_t &date, char *filename = 0, int filename_len = 0);
+	bool _open_for_transmit();
+	size_t _get_log_data(uint8_t len, uint8_t *buffer);
+	void _close_and_unlink_files();
+
 	size_t _log_send_listing();
 	size_t _log_send_data();
 
-	LogListHelper    *_pLogHandlerHelper;
+	LogHandlerState _current_status{LogHandlerState::Inactive};
 	Mavlink *_mavlink;
+
+	int         _next_entry{0};
+	int         _last_entry{0};
+	int         _log_count{0};
+
+	uint16_t    _current_log_index{UINT16_MAX};
+	uint32_t    _current_log_size{0};
+	uint32_t    _current_log_data_offset{0};
+	uint32_t    _current_log_data_remaining{0};
+	FILE       *_current_log_filep{nullptr};
+	char        _current_log_filename[128]; //TODO: consider to allocate on runtime
 };