ble_image_transfer_service.c

/**
 * Copyright (c) 2012 - 2017, Nordic Semiconductor ASA
 * 
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form, except as embedded into a Nordic
 *    Semiconductor ASA integrated circuit in a product or a software update for
 *    such product, must reproduce the above copyright notice, this list of
 *    conditions and the following disclaimer in the documentation and/or other
 *    materials provided with the distribution.
 * 
 * 3. Neither the name of Nordic Semiconductor ASA nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 * 
 * 4. This software, with or without modification, must only be used with a
 *    Nordic Semiconductor ASA integrated circuit.
 * 
 * 5. Any software provided in binary form under this license must not be reverse
 *    engineered, decompiled, modified and/or disassembled.
 * 
 * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 */
#include <stdio.h>
#include "sdk_common.h"
#if NRF_MODULE_ENABLED(BLE_NUS)
#include "ble_image_transfer_service.h"
#include "ble_srv_common.h"
#include "ble.h"
#include "nrf_gpio.h"

#define BLE_UUID_ITS_TX_CHARACTERISTIC 0x0003                      /**< The UUID of the TX Characteristic. */
#define BLE_UUID_ITS_RX_CHARACTERISTIC 0x0002                      /**< The UUID of the RX Characteristic. */
#define BLE_UUID_ITS_IMG_INFO_CHARACTERISTIC 0x0004

#define BLE_ITS_MAX_RX_CHAR_LEN        BLE_ITS_MAX_DATA_LEN        /**< Maximum length of the RX Characteristic (in bytes). */
#define BLE_ITS_MAX_TX_CHAR_LEN        BLE_ITS_MAX_DATA_LEN        /**< Maximum length of the TX Characteristic (in bytes). */

#define ITS_BASE_UUID                  {{0x3E, 0xCA, 0xDC, 0x24, 0x0E, 0xE5, 0xA9, 0xE0, 0x93, 0xF3, 0xA3, 0xB5, 0x00, 0x00, 0x40, 0x6E}} /**< Used vendor specific UUID. */

#include "nrf_log.h"

volatile uint32_t file_size = 0, file_pos = 0, m_max_data_length = 20;
uint8_t * file_data;
ble_its_t * m_its;

#define ITS_ENABLE_PIN_DEBUGGING 0

#if(ITS_ENABLE_PIN_DEBUGGING == 1)
#define ITS_DEBUG_PIN_SET(_pin) nrf_gpio_pin_set(DBG_PIN_ ## _pin)
#define ITS_DEBUG_PIN_CLR(_pin) nrf_gpio_pin_clear(DBG_PIN_ ## _pin)
#else
#define ITS_DEBUG_PIN_SET(_pin) 
#define ITS_DEBUG_PIN_CLR(_pin) 
#endif

static void its_enable_gpio_debug(void)
{
#if(ITS_ENABLE_PIN_DEBUGGING == 1)
    nrf_gpio_cfg_output(DBG_PIN_0);
    nrf_gpio_cfg_output(DBG_PIN_1);
    nrf_gpio_cfg_output(DBG_PIN_2);
    
    // Configure two GPIO's to signal TX and RX activity on the radio, for debugging throughput issues on different phones
    NRF_GPIOTE->CONFIG[0] = GPIOTE_CONFIG_MODE_Task << GPIOTE_CONFIG_MODE_Pos |
                            GPIOTE_CONFIG_POLARITY_Toggle << GPIOTE_CONFIG_POLARITY_Pos | 
                            DBG_PIN_3 << GPIOTE_CONFIG_PSEL_Pos;
    NRF_GPIOTE->CONFIG[1] = GPIOTE_CONFIG_MODE_Task << GPIOTE_CONFIG_MODE_Pos |
                            GPIOTE_CONFIG_POLARITY_Toggle << GPIOTE_CONFIG_POLARITY_Pos | 
                            DBG_PIN_4 << GPIOTE_CONFIG_PSEL_Pos;
    
    NRF_PPI->CH[0].EEP = (uint32_t)&NRF_RADIO->EVENTS_TXREADY;
    NRF_PPI->CH[0].TEP = (uint32_t)&NRF_GPIOTE->TASKS_SET[0];
    
    NRF_PPI->CH[1].EEP = (uint32_t)&NRF_RADIO->EVENTS_RXREADY;
    NRF_PPI->CH[1].TEP = (uint32_t)&NRF_GPIOTE->TASKS_SET[1];
    
    NRF_PPI->CH[2].EEP = (uint32_t)&NRF_RADIO->EVENTS_DISABLED;
    NRF_PPI->CH[2].TEP = (uint32_t)&NRF_GPIOTE->TASKS_CLR[0];
    NRF_PPI->FORK[2].TEP = (uint32_t)&NRF_GPIOTE->TASKS_CLR[1];
    
    NRF_PPI->CHENSET = 0x07;
#endif
}


/**@brief Function for handling the @ref BLE_GAP_EVT_CONNECTED event from the S110 SoftDevice.
 *
 * @param[in] p_its     Nordic UART Service structure.
 * @param[in] p_ble_evt Pointer to the event received from BLE stack.
 */
static void on_connect(ble_its_t * p_its, ble_evt_t const * p_ble_evt)
{
    p_its->conn_handle = p_ble_evt->evt.gap_evt.conn_handle;
}


/**@brief Function for handling the @ref BLE_GAP_EVT_DISCONNECTED event from the S110 SoftDevice.
 *
 * @param[in] p_its     Nordic UART Service structure.
 * @param[in] p_ble_evt Pointer to the event received from BLE stack.
 */
static void on_disconnect(ble_its_t * p_its, ble_evt_t const * p_ble_evt)
{
    UNUSED_PARAMETER(p_ble_evt);
    p_its->conn_handle = BLE_CONN_HANDLE_INVALID;
}


/**@brief Function for handling the @ref BLE_GATTS_EVT_WRITE event from the S110 SoftDevice.
 *
 * @param[in] p_its     Nordic UART Service structure.
 * @param[in] p_ble_evt Pointer to the event received from BLE stack.
 */
static void on_write(ble_its_t * p_its, ble_evt_t const * p_ble_evt)
{
    ble_gatts_evt_write_t const * p_evt_write = &p_ble_evt->evt.gatts_evt.params.write;

    if (
        (p_evt_write->handle == p_its->tx_handles.cccd_handle)
        &&
        (p_evt_write->len == 2)
       )
    {
        if (ble_srv_is_notification_enabled(p_evt_write->data))
        {
            p_its->is_notification_enabled = true;
        }
        else
        {
            p_its->is_notification_enabled = false;
        }
    }
    else if (
        (p_evt_write->handle == p_its->img_info_handles.cccd_handle)
        &&
        (p_evt_write->len == 2)
       )
    {
        if (ble_srv_is_notification_enabled(p_evt_write->data))
        {
            p_its->is_info_char_notification_enabled = true;
        }
        else
        {
            p_its->is_info_char_notification_enabled = false;
        }
    }
    else if (
             (p_evt_write->handle == p_its->rx_handles.value_handle)
             &&
             (p_its->data_handler != NULL)
            )
    {
        p_its->data_handler(p_its, p_evt_write->data, p_evt_write->len);
    }
    else
    {
        // Do Nothing. This event is not relevant for this service.
    }
}


/**@brief Function for adding TX characteristic.
 *
 * @param[in] p_its       Nordic UART Service structure.
 * @param[in] p_its_init  Information needed to initialize the service.
 *
 * @return NRF_SUCCESS on success, otherwise an error code.
 */
static uint32_t tx_char_add(ble_its_t * p_its, const ble_its_init_t * p_its_init)
{
    /**@snippet [Adding proprietary characteristic to S110 SoftDevice] */
    ble_gatts_char_md_t char_md;
    ble_gatts_attr_md_t cccd_md;
    ble_gatts_attr_t    attr_char_value;
    ble_uuid_t          ble_uuid;
    ble_gatts_attr_md_t attr_md;

    memset(&cccd_md, 0, sizeof(cccd_md));

    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.write_perm);

    cccd_md.vloc = BLE_GATTS_VLOC_STACK;

    memset(&char_md, 0, sizeof(char_md));

    char_md.char_props.notify = 1;
    char_md.p_char_user_desc  = NULL;
    char_md.p_char_pf         = NULL;
    char_md.p_user_desc_md    = NULL;
    char_md.p_cccd_md         = &cccd_md;
    char_md.p_sccd_md         = NULL;

    ble_uuid.type = p_its->uuid_type;
    ble_uuid.uuid = BLE_UUID_ITS_TX_CHARACTERISTIC;

    memset(&attr_md, 0, sizeof(attr_md));

    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.write_perm);

    attr_md.vloc    = BLE_GATTS_VLOC_STACK;
    attr_md.rd_auth = 0;
    attr_md.wr_auth = 0;
    attr_md.vlen    = 1;

    memset(&attr_char_value, 0, sizeof(attr_char_value));

    attr_char_value.p_uuid    = &ble_uuid;
    attr_char_value.p_attr_md = &attr_md;
    attr_char_value.init_len  = sizeof(uint8_t);
    attr_char_value.init_offs = 0;
    attr_char_value.max_len   = BLE_ITS_MAX_TX_CHAR_LEN;

    return sd_ble_gatts_characteristic_add(p_its->service_handle,
                                           &char_md,
                                           &attr_char_value,
                                           &p_its->tx_handles);
    /**@snippet [Adding proprietary characteristic to S110 SoftDevice] */
}

/**@brief Function for adding TX characteristic.
 *
 * @param[in] p_its       Nordic UART Service structure.
 * @param[in] p_its_init  Information needed to initialize the service.
 *
 * @return NRF_SUCCESS on success, otherwise an error code.
 */
static uint32_t img_info_char_add(ble_its_t * p_its, const ble_its_init_t * p_its_init)
{
    /**@snippet [Adding proprietary characteristic to S110 SoftDevice] */
    ble_gatts_char_md_t char_md;
    ble_gatts_attr_md_t cccd_md;
    ble_gatts_attr_t    attr_char_value;
    ble_uuid_t          ble_uuid;
    ble_gatts_attr_md_t attr_md;

    memset(&cccd_md, 0, sizeof(cccd_md));

    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.write_perm);

    cccd_md.vloc = BLE_GATTS_VLOC_STACK;

    memset(&char_md, 0, sizeof(char_md));

    char_md.char_props.notify = 1;
    char_md.p_char_user_desc  = NULL;
    char_md.p_char_pf         = NULL;
    char_md.p_user_desc_md    = NULL;
    char_md.p_cccd_md         = &cccd_md;
    char_md.p_sccd_md         = NULL;

    ble_uuid.type = p_its->uuid_type;
    ble_uuid.uuid = BLE_UUID_ITS_IMG_INFO_CHARACTERISTIC;

    memset(&attr_md, 0, sizeof(attr_md));

    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.write_perm);

    attr_md.vloc    = BLE_GATTS_VLOC_STACK;
    attr_md.rd_auth = 0;
    attr_md.wr_auth = 0;
    attr_md.vlen    = 1;

    memset(&attr_char_value, 0, sizeof(attr_char_value));

    attr_char_value.p_uuid    = &ble_uuid;
    attr_char_value.p_attr_md = &attr_md;
    attr_char_value.init_len  = 1 + sizeof(ble_its_img_info_t);
    attr_char_value.init_offs = 0;
    attr_char_value.max_len   = 16;

    return sd_ble_gatts_characteristic_add(p_its->service_handle,
                                           &char_md,
                                           &attr_char_value,
                                           &p_its->img_info_handles);
    /**@snippet [Adding proprietary characteristic to S110 SoftDevice] */
}


/**@brief Function for adding RX characteristic.
 *
 * @param[in] p_its       Nordic UART Service structure.
 * @param[in] p_its_init  Information needed to initialize the service.
 *
 * @return NRF_SUCCESS on success, otherwise an error code.
 */
static uint32_t rx_char_add(ble_its_t * p_its, const ble_its_init_t * p_its_init)
{
    ble_gatts_char_md_t char_md;
    ble_gatts_attr_t    attr_char_value;
    ble_uuid_t          ble_uuid;
    ble_gatts_attr_md_t attr_md;

    memset(&char_md, 0, sizeof(char_md));

    char_md.char_props.write         = 1;
    char_md.char_props.write_wo_resp = 1;
    char_md.p_char_user_desc         = NULL;
    char_md.p_char_pf                = NULL;
    char_md.p_user_desc_md           = NULL;
    char_md.p_cccd_md                = NULL;
    char_md.p_sccd_md                = NULL;

    ble_uuid.type = p_its->uuid_type;
    ble_uuid.uuid = BLE_UUID_ITS_RX_CHARACTERISTIC;

    memset(&attr_md, 0, sizeof(attr_md));

    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.write_perm);

    attr_md.vloc    = BLE_GATTS_VLOC_STACK;
    attr_md.rd_auth = 0;
    attr_md.wr_auth = 0;
    attr_md.vlen    = 1;

    memset(&attr_char_value, 0, sizeof(attr_char_value));

    attr_char_value.p_uuid    = &ble_uuid;
    attr_char_value.p_attr_md = &attr_md;
    attr_char_value.init_len  = 1;
    attr_char_value.init_offs = 0;
    attr_char_value.max_len   = BLE_ITS_MAX_RX_CHAR_LEN;

    return sd_ble_gatts_characteristic_add(p_its->service_handle,
                                           &char_md,
                                           &attr_char_value,
                                           &p_its->rx_handles);
}


static uint32_t push_data_packets()
{
    uint32_t return_code = NRF_SUCCESS;
    uint32_t packet_length = m_max_data_length;
    uint32_t packet_size = 0;
    ITS_DEBUG_PIN_SET(1);
    while(return_code == NRF_SUCCESS)
    {
        if((file_size - file_pos) > packet_length)
        {
            packet_size = packet_length;
        }
        else if((file_size - file_pos) > 0)
        {
            packet_size = file_size - file_pos;
        }
        
        if(packet_size > 0)
        {
            return_code = ble_its_string_send(m_its, &file_data[file_pos], packet_size);
            if(return_code == NRF_SUCCESS)
            {
                file_pos += packet_size;
            }   
        }
        else
        {
            file_size = 0;
            break;
        }
    }
    ITS_DEBUG_PIN_CLR(1);
    return return_code;
}

static volatile bool nrf_error_resources = false;

void ble_its_on_ble_evt(ble_evt_t const * p_ble_evt, void * p_context)
{
    if ((p_context == NULL) || (p_ble_evt == NULL))
    {
        return;
    }
    
    ble_its_t * p_its = (ble_its_t*)p_context;
    
    switch (p_ble_evt->header.evt_id)
    {
        case BLE_GAP_EVT_CONNECTED:
            on_connect(p_its, p_ble_evt);
            break;

        case BLE_GAP_EVT_DISCONNECTED:
            on_disconnect(p_its, p_ble_evt);
            break;

        case BLE_GATTS_EVT_WRITE:
            on_write(p_its, p_ble_evt);
            break;

        case BLE_GATTS_EVT_HVN_TX_COMPLETE:
            {
                //uint32_t count = p_ble_evt->evt.gatts_evt.params.hvn_tx_complete.count;
                ITS_DEBUG_PIN_SET(2);
                ITS_DEBUG_PIN_CLR(1);
                if(file_size > 0)
                {
                    push_data_packets();
                }
                ITS_DEBUG_PIN_CLR(2);
                nrf_error_resources = false;
            }
            break;
            
        default:
            // No implementation needed.
            break;
    }
}


uint32_t ble_its_init(ble_its_t * p_its, const ble_its_init_t * p_its_init)
{
    uint32_t      err_code;
    ble_uuid_t    ble_uuid;
    ble_uuid128_t its_base_uuid = ITS_BASE_UUID;

    VERIFY_PARAM_NOT_NULL(p_its);
    VERIFY_PARAM_NOT_NULL(p_its_init);

    // Initialize the service structure.
    p_its->conn_handle             = BLE_CONN_HANDLE_INVALID;
    p_its->data_handler            = p_its_init->data_handler;
    p_its->is_notification_enabled = false;

    /**@snippet [Adding proprietary Service to S110 SoftDevice] */
    // Add a custom base UUID.
    err_code = sd_ble_uuid_vs_add(&its_base_uuid, &p_its->uuid_type);
    VERIFY_SUCCESS(err_code);

    ble_uuid.type = p_its->uuid_type;
    ble_uuid.uuid = BLE_UUID_ITS_SERVICE;

    // Add the service.
    err_code = sd_ble_gatts_service_add(BLE_GATTS_SRVC_TYPE_PRIMARY,
                                        &ble_uuid,
                                        &p_its->service_handle);
    /**@snippet [Adding proprietary Service to S110 SoftDevice] */
    VERIFY_SUCCESS(err_code);

    // Add the RX Characteristic.
    err_code = rx_char_add(p_its, p_its_init);
    VERIFY_SUCCESS(err_code);

    // Add the TX Characteristic.
    err_code = tx_char_add(p_its, p_its_init);
    VERIFY_SUCCESS(err_code);
    
    // Add the Image Info Characteristic.
    err_code = img_info_char_add(p_its, p_its_init);
    VERIFY_SUCCESS(err_code);

    its_enable_gpio_debug();
    return NRF_SUCCESS;
}


uint32_t ble_its_string_send(ble_its_t * p_its, uint8_t * p_string, uint16_t length)
{
    ble_gatts_hvx_params_t hvx_params;
    uint32_t err_code;
    ITS_DEBUG_PIN_SET(0);

    if(nrf_error_resources)
    {
        ITS_DEBUG_PIN_CLR(0);
        return NRF_ERROR_RESOURCES;
    }

    VERIFY_PARAM_NOT_NULL(p_its);

    if ((p_its->conn_handle == BLE_CONN_HANDLE_INVALID) || (!p_its->is_notification_enabled))
    {
        return NRF_ERROR_INVALID_STATE;
    }

    if (length > BLE_ITS_MAX_DATA_LEN)
    {
        return NRF_ERROR_INVALID_PARAM;
    }

    memset(&hvx_params, 0, sizeof(hvx_params));
    hvx_params.handle = p_its->tx_handles.value_handle;
    hvx_params.p_data = p_string;
    hvx_params.p_len  = &length;
    hvx_params.type   = BLE_GATT_HVX_NOTIFICATION;
    
    err_code = sd_ble_gatts_hvx(p_its->conn_handle, &hvx_params);

    if(err_code == NRF_ERROR_RESOURCES)
    {
        nrf_error_resources = true;
        ITS_DEBUG_PIN_SET(1);
    }
    ITS_DEBUG_PIN_CLR(0);
    //NRF_LOG_INFO("NOT - Len: %i, err_code: %i", length, err_code);
    return err_code;
}

uint32_t ble_its_ble_params_info_send(ble_its_t * p_its, ble_its_ble_params_info_t * ble_params_info)
{
    uint8_t data_buf[1 + sizeof(ble_its_ble_params_info_t)];
    ble_gatts_hvx_params_t hvx_params;

    VERIFY_PARAM_NOT_NULL(p_its);

    if ((p_its->conn_handle == BLE_CONN_HANDLE_INVALID) || (!p_its->is_info_char_notification_enabled))
    {
        return NRF_ERROR_INVALID_STATE;
    }

    uint16_t length = 1 + sizeof(ble_its_ble_params_info_t);

    data_buf[0] = 2;
    memcpy(&data_buf[1], ble_params_info, sizeof(ble_its_ble_params_info_t));
    
    memset(&hvx_params, 0, sizeof(hvx_params));
    
    hvx_params.handle = p_its->img_info_handles.value_handle;
    hvx_params.p_data = data_buf;
    hvx_params.p_len  = &length;
    hvx_params.type   = BLE_GATT_HVX_NOTIFICATION;

    return sd_ble_gatts_hvx(p_its->conn_handle, &hvx_params);     
}

uint32_t ble_its_img_info_send(ble_its_t * p_its, ble_its_img_info_t * img_info)
{
    uint8_t data_buf[1 + sizeof(ble_its_img_info_t)];
    ble_gatts_hvx_params_t hvx_params;

    VERIFY_PARAM_NOT_NULL(p_its);

    if ((p_its->conn_handle == BLE_CONN_HANDLE_INVALID) || (!p_its->is_info_char_notification_enabled))
    {
        return NRF_ERROR_INVALID_STATE;
    }

    uint16_t length = 1 + sizeof(ble_its_img_info_t);

    data_buf[0] = 1;
    memcpy(&data_buf[1], img_info, sizeof(ble_its_img_info_t));
    
    memset(&hvx_params, 0, sizeof(hvx_params));
    
    hvx_params.handle = p_its->img_info_handles.value_handle;
    hvx_params.p_data = data_buf;
    hvx_params.p_len  = &length;
    hvx_params.type   = BLE_GATT_HVX_NOTIFICATION;

    return sd_ble_gatts_hvx(p_its->conn_handle, &hvx_params);    
}


uint32_t ble_its_send_file(ble_its_t * p_its, uint8_t * p_data, uint32_t data_length, uint32_t max_packet_length)
{
    uint32_t err_code; 
    
    if ((p_its->conn_handle == BLE_CONN_HANDLE_INVALID) || (!p_its->is_notification_enabled))
    {
        return NRF_ERROR_INVALID_STATE;
    } 
    
    if(file_size != 0)
    {
        return NRF_ERROR_BUSY;
    }
    
    ble_its_img_info_t image_info;
    image_info.file_size_bytes = data_length;
    ble_its_img_info_send(p_its, &image_info);
    
    file_size = data_length;
    file_pos = 0;
    file_data = p_data;
    m_max_data_length = max_packet_length;
    m_its = p_its;
   
    err_code = push_data_packets();
    if(err_code == NRF_ERROR_RESOURCES) return NRF_SUCCESS;
    return err_code;
}


uint32_t ble_its_send_file_fragment(ble_its_t * p_its, uint8_t * p_data, uint32_t data_length)
{
    uint32_t err_code; 
    
    if ((p_its->conn_handle == BLE_CONN_HANDLE_INVALID) || (!p_its->is_notification_enabled))
    {
        return NRF_ERROR_INVALID_STATE;
    } 
    
    if(file_size != 0)
    {
        return NRF_ERROR_BUSY;
    }
    
    err_code = ble_its_string_send(p_its, p_data, data_length);           
    return err_code;
}


bool ble_its_file_transfer_busy(void)
{
    return file_size != 0;
}

#endif // NRF_MODULE_ENABLED(BLE_NUS)