Function esp_https_ota_get_bootloader_img_desc 

pub unsafe extern "C" fn esp_https_ota_get_bootloader_img_desc(
    https_ota_handle: esp_https_ota_handle_t,
    new_img_info: *mut esp_bootloader_desc_t,
) -> esp_err_t

@brief Reads bootloader description from image header. The bootloader description provides information like the “Bootloader version” of the image.

@note This API can be called only after esp_https_ota_begin() and before esp_https_ota_perform(). Calling this API is not mandatory.

@param[in] https_ota_handle pointer to esp_https_ota_handle_t structure @param[out] new_img_info pointer to an allocated esp_bootloader_desc_t structure

@return

• ESP_ERR_INVALID_ARG: Invalid arguments
• ESP_ERR_INVALID_STATE: Invalid state to call this API. esp_https_ota_begin() not called yet.
• ESP_FAIL: Failed to read image descriptor
• ESP_OK: Successfully read image descriptor