# LwFTP Client

A lightweight FTP client using FreeRTOS and the Netconn API from LwIP, designed for STM32 H7.

## About The Project

This project aims to provide a simple FTP client for embedded systems, enabling file operations over a network. It's built for systems running FreeRTOS and uses the Netconn API from LwIP for network communication.

### Prerequisites:

- STM32 H7 microcontroller
- An FTP Server (tested with Windows IIS Server Manager)
- FreeRTOS
- LwIP with Netconn API (requires RTOS mode)
- This repository

## Initialization

To initialize the LwFTP client, follow these steps:

1. **Add the following declarations in the `/* USER CODE BEGIN PV */` sections**
    ```C
    /* USER CODE BEGIN PV */
    static lwftp_session_t s;
    uint8_t CLI_IP[4] = { 192, 168, 0, 120 };    // Client IP address
    uint8_t SVR_IP[4] = { 192, 168, 0, 100 };    // Server IP address
    u16_t SVR_PORT = 21;                         // FTP server port, typically 21
    char *USER = "anonymous";                    // FTP login username
    char *PASS = "email@example.com";            // FTP login password
    /* USER CODE END PV */
    ```

2. **Declare `lwftp_init()` in the main file**

    example:

    ```c
    void lwftp_init(void) {
        IP4_ADDR(&s.cli_ip, CLI_IP[0], CLI_IP[1], CLI_IP[2], CLI_IP[3]);
        IP4_ADDR(&s.svr_ip, SVR_IP[0], SVR_IP[1], SVR_IP[2], SVR_IP[3]);
        s.svr_port = SVR_PORT;
        s.user = USER;
        s.pass = PASS;

        debugPrint("\n>> lwftp: cli ip: %d.%d.%d.%d\r\n", CLI_IP[0], CLI_IP[1], CLI_IP[2], CLI_IP[3]);
        debugPrint(">> lwftp: svr ip: %d.%d.%d.%d\r\n", SVR_IP[0], SVR_IP[1], SVR_IP[2], SVR_IP[3]);
        debugPrint(">> lwftp: svr port: %d\r\n", s.svr_port);
        debugPrint(">> lwftp: username: %s\r\n", s.user);
        debugPrint(">> lwftp: password: %s\r\n\n", s.pass);

        // Initialize threads for FTP connections
        sys_thread_new("lwftp_ctrl_thread", lwftp_ctrl_thread, (void*) &s, DEFAULT_THREAD_STACKSIZE, osPriorityNormal);
        sys_thread_new("lwftp_data_thread", lwftp_data_thread, (void*) &s, DEFAULT_THREAD_STACKSIZE, osPriorityNormal);
    }
    ```

3. **Call `lwftp_init()` from the user code area** of `StartDefaultTask()` in `main.c`, right after `MX_LWIP_Init()`

    example:

    ```c
    void StartDefaultTask(void const * argument)
    {
        /* init code for LWIP */
        MX_LWIP_Init();
        /* USER CODE BEGIN 5 */
        lwftp_init();
        /* Infinite loop */
        for (;;) {
            osDelay(1);
        }
        /* USER CODE END 5 */
    }
    ```
## Main Features & Limitations

- **Storing Files:** `err = lwftp_store(&s, <filename.extension>, <data>);`
    - *Under development:* A feature to prevent overwriting duplicate files.

- **Retrieving Files:** `err = lwftp_retrieve(&s, <filename.extension>);`
    - *Limitation:* May omit excessively long content. This issue is pending resolution.

- **Listing Files:** `err = lwftp_list(&s, fileList);`
    - To retrieve a list of files from the server's root directory, declare a character array (e.g., `char *fileList[500];`) and pass it as an argument.
    - *Note:* Path specification is not implemented. 
    - *Note:* The output format of the file list may vary between servers, requiring careful parsing.

- **Closing Connection:** `err = lwftp_close(&s);`
    - closes the FTP connection.

## Features for debugging

- **Enabling LwFTP Debugging Output**

  To enable verbose debugging output for LwFTP, modify the `LWFTP_DEBUG` comment value in `lwftp.h`.