text: // Copyright 2018 Espressif Systems (Shanghai) PTE LTD
  //
  // Licensed under the Apache License, Version 2.0 (the "License");
  // you may not use this file except in compliance with the License.
  // You may obtain a copy of the License at
  //
  //     http://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing, software
  // distributed under the License is distributed on an "AS IS" BASIS,
  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  // See the License for the specific language governing permissions and
  // limitations under the License.
  
  #pragma once
  #include "esp_flash_data_types.h"
  #include "esp_image_format.h"
  
  /// Type of hold a GPIO in low state
  typedef enum {
      GPIO_LONG_HOLD  = 1,    /*!< The long hold GPIO */
      GPIO_SHORT_HOLD = -1,   /*!< The short hold GPIO */
      GPIO_NOT_HOLD   = 0     /*!< If the GPIO input is not low */
  } esp_comm_gpio_hold_t;
  
  /**
   * @brief Calculate crc for the OTA data select.
   *
   * @param[in] s The OTA data select.
   * @return    Returns crc value.
   */
  uint32_t bootloader_common_ota_select_crc(const esp_ota_select_entry_t *s);
  
  /**
   * @brief Verifies the validity of the OTA data select
   *
   * @param[in] s The OTA data select.
   * @return    Returns true on valid, false otherwise.
   */
  bool bootloader_common_ota_select_valid(const esp_ota_select_entry_t *s);
  
  /**
   * @brief Returns true if OTADATA is not marked as bootable partition.
   *
   * @param[in] s The OTA data select.
   * @return    Returns true if OTADATA invalid, false otherwise.
   */
  bool bootloader_common_ota_select_invalid(const esp_ota_select_entry_t *s);
  
  /**
   * @brief Check if the GPIO input is a long hold or a short hold.
   *
   * Number of the GPIO input will be configured as an input with internal pull-up enabled.
   * If the GPIO input is held low continuously for delay_sec period then it is a long hold.
   * If the GPIO input is held low for less period then it is a short hold.
   *
   * @param[in] num_pin Number of the GPIO input.
   * @param[in] delay_sec Input must be driven low for at least this long, continuously.
   * @return esp_comm_gpio_hold_t Defines type of hold a GPIO in low state.
   */
  esp_comm_gpio_hold_t bootloader_common_check_long_hold_gpio(uint32_t num_pin, uint32_t delay_sec);
  
  /**
   * @brief Erase the partition data that is specified in the transferred list.
   *
   * @param[in] list_erase String containing a list of cleared partitions. Like this "nvs, phy". The string must be null-terminal.
   * @param[in] ota_data_erase If true then the OTA data partition will be cleared (if there is it in partition table).
   * @return    Returns true on success, false otherwise.
   */
  bool bootloader_common_erase_part_type_data(const char *list_erase, bool ota_data_erase);
  
  /**
   * @brief Determines if the list contains the label
   *
   * @param[in] list  A string of names delimited by commas or spaces. Like this "nvs, phy, data". The string must be null-terminated.
   * @param[in] label The substring that will be searched in the list.
   * @return    Returns true if the list contains the label, false otherwise.
   */
  bool bootloader_common_label_search(const char *list, char *label);
  
  /**
   * @brief Calculates a sha-256 for a given partition or returns a appended digest.
   *
   * This function can be used to return the SHA-256 digest of application, bootloader and data partitions.
   * For apps with SHA-256 appended to the app image, the result is the appended SHA-256 value for the app image content.
   * The hash is verified before returning, if app content is invalid then the function returns ESP_ERR_IMAGE_INVALID.
   * For apps without SHA-256 appended to the image, the result is the SHA-256 of all bytes in the app image.
   * For other partition types, the result is the SHA-256 of the entire partition.
   *
   * @param[in]  address      Address of partition.
   * @param[in]  size         Size of partition.
   * @param[in]  type         Type of partition. For applications the type is 0, otherwise type is data.
   * @param[out] out_sha_256  Returned SHA-256 digest for a given partition.
   *
   * @return
   *          - ESP_OK: In case of successful operation.
   *          - ESP_ERR_INVALID_ARG: The size was 0 or the sha_256 was NULL.
   *          - ESP_ERR_NO_MEM: Cannot allocate memory for sha256 operation.
   *          - ESP_ERR_IMAGE_INVALID: App partition doesn't contain a valid app image.
   *          - ESP_FAIL: An allocation error occurred.
   */
  esp_err_t bootloader_common_get_sha256_of_partition(uint32_t address, uint32_t size, int type, uint8_t *out_sha_256);
  
  /**
   * @brief Returns the number of active otadata.
   *
   * @param[in] two_otadata Pointer on array from two otadata structures.
   *
   * @return The number of active otadata (0 or 1).
   *        - -1: If it does not have active otadata.
   */
  int bootloader_common_get_active_otadata(esp_ota_select_entry_t *two_otadata);
  
  /**
   * @brief Returns the number of active otadata.
   *
   * @param[in] two_otadata       Pointer on array from two otadata structures.
   * @param[in] valid_two_otadata Pointer on array from two bools. True means select.
   * @param[in] max               True - will select the maximum ota_seq number, otherwise the minimum.
   *
   * @return The number of active otadata (0 or 1).
   *        - -1: If it does not have active otadata.
   */
  int bootloader_common_select_otadata(const esp_ota_select_entry_t *two_otadata, bool *valid_two_otadata, bool max);
  
  /**
   * @brief Returns esp_app_desc structure for app partition. This structure includes app version.
   * 
   * Returns a description for the requested app partition.
   * @param[in] partition      App partition description.
   * @param[out] app_desc      Structure of info about app.
   * @return
   *  - ESP_OK:                Successful.
   *  - ESP_ERR_INVALID_ARG:   The arguments passed are not valid.
   *  - ESP_ERR_NOT_FOUND:     app_desc structure is not found. Magic word is incorrect.
   *  - ESP_FAIL:              mapping is fail.
   */
  esp_err_t bootloader_common_get_partition_description(const esp_partition_pos_t *partition, esp_app_desc_t *app_desc);
  