mirror of
https://github.com/espressif/esp-idf.git
synced 2024-10-05 20:47:46 -04:00
c93626db3f
Users needs functions to count the number of free and used entries. 1. `nvs_get_stats()` This function return structure of statistic about the uspace NVS. (Struct: used_entries, free_entries, total_entries and namespace_count) 2. `nvs_get_used_entry_count()` The second function return amount of entries in the namespace (by handler) 3. Added unit tests. Closes TW<12282>
448 lines
22 KiB
C
448 lines
22 KiB
C
// Copyright 2015-2016 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.
|
||
#ifndef ESP_NVS_H
|
||
#define ESP_NVS_H
|
||
|
||
#include <stdint.h>
|
||
#include <stddef.h>
|
||
#include <stdbool.h>
|
||
#include "esp_err.h"
|
||
|
||
#ifdef __cplusplus
|
||
extern "C" {
|
||
#endif
|
||
|
||
/**
|
||
* Opaque pointer type representing non-volatile storage handle
|
||
*/
|
||
typedef uint32_t nvs_handle;
|
||
|
||
#define ESP_ERR_NVS_BASE 0x1100 /*!< Starting number of error codes */
|
||
#define ESP_ERR_NVS_NOT_INITIALIZED (ESP_ERR_NVS_BASE + 0x01) /*!< The storage driver is not initialized */
|
||
#define ESP_ERR_NVS_NOT_FOUND (ESP_ERR_NVS_BASE + 0x02) /*!< Id namespace doesn’t exist yet and mode is NVS_READONLY */
|
||
#define ESP_ERR_NVS_TYPE_MISMATCH (ESP_ERR_NVS_BASE + 0x03) /*!< The type of set or get operation doesn't match the type of value stored in NVS */
|
||
#define ESP_ERR_NVS_READ_ONLY (ESP_ERR_NVS_BASE + 0x04) /*!< Storage handle was opened as read only */
|
||
#define ESP_ERR_NVS_NOT_ENOUGH_SPACE (ESP_ERR_NVS_BASE + 0x05) /*!< There is not enough space in the underlying storage to save the value */
|
||
#define ESP_ERR_NVS_INVALID_NAME (ESP_ERR_NVS_BASE + 0x06) /*!< Namespace name doesn’t satisfy constraints */
|
||
#define ESP_ERR_NVS_INVALID_HANDLE (ESP_ERR_NVS_BASE + 0x07) /*!< Handle has been closed or is NULL */
|
||
#define ESP_ERR_NVS_REMOVE_FAILED (ESP_ERR_NVS_BASE + 0x08) /*!< The value wasn’t updated because flash write operation has failed. The value was written however, and update will be finished after re-initialization of nvs, provided that flash operation doesn’t fail again. */
|
||
#define ESP_ERR_NVS_KEY_TOO_LONG (ESP_ERR_NVS_BASE + 0x09) /*!< Key name is too long */
|
||
#define ESP_ERR_NVS_PAGE_FULL (ESP_ERR_NVS_BASE + 0x0a) /*!< Internal error; never returned by nvs_ API functions */
|
||
#define ESP_ERR_NVS_INVALID_STATE (ESP_ERR_NVS_BASE + 0x0b) /*!< NVS is in an inconsistent state due to a previous error. Call nvs_flash_init and nvs_open again, then retry. */
|
||
#define ESP_ERR_NVS_INVALID_LENGTH (ESP_ERR_NVS_BASE + 0x0c) /*!< String or blob length is not sufficient to store data */
|
||
#define ESP_ERR_NVS_NO_FREE_PAGES (ESP_ERR_NVS_BASE + 0x0d) /*!< NVS partition doesn't contain any empty pages. This may happen if NVS partition was truncated. Erase the whole partition and call nvs_flash_init again. */
|
||
#define ESP_ERR_NVS_VALUE_TOO_LONG (ESP_ERR_NVS_BASE + 0x0e) /*!< String or blob length is longer than supported by the implementation */
|
||
#define ESP_ERR_NVS_PART_NOT_FOUND (ESP_ERR_NVS_BASE + 0x0f) /*!< Partition with specified name is not found in the partition table */
|
||
|
||
#define NVS_DEFAULT_PART_NAME "nvs" /*!< Default partition name of the NVS partition in the partition table */
|
||
/**
|
||
* @brief Mode of opening the non-volatile storage
|
||
*
|
||
*/
|
||
typedef enum {
|
||
NVS_READONLY, /*!< Read only */
|
||
NVS_READWRITE /*!< Read and write */
|
||
} nvs_open_mode;
|
||
|
||
/**
|
||
* @brief Open non-volatile storage with a given namespace from the default NVS partition
|
||
*
|
||
* Multiple internal ESP-IDF and third party application modules can store
|
||
* their key-value pairs in the NVS module. In order to reduce possible
|
||
* conflicts on key names, each module can use its own namespace.
|
||
* The default NVS partition is the one that is labelled "nvs" in the partition
|
||
* table.
|
||
*
|
||
* @param[in] name Namespace name. Maximal length is determined by the
|
||
* underlying implementation, but is guaranteed to be
|
||
* at least 15 characters. Shouldn't be empty.
|
||
* @param[in] open_mode NVS_READWRITE or NVS_READONLY. If NVS_READONLY, will
|
||
* open a handle for reading only. All write requests will
|
||
* be rejected for this handle.
|
||
* @param[out] out_handle If successful (return code is zero), handle will be
|
||
* returned in this argument.
|
||
*
|
||
* @return
|
||
* - ESP_OK if storage handle was opened successfully
|
||
* - ESP_ERR_NVS_NOT_INITIALIZED if the storage driver is not initialized
|
||
* - ESP_ERR_NVS_PART_NOT_FOUND if the partition with label "nvs" is not found
|
||
* - ESP_ERR_NVS_NOT_FOUND id namespace doesn't exist yet and
|
||
* mode is NVS_READONLY
|
||
* - ESP_ERR_NVS_INVALID_NAME if namespace name doesn't satisfy constraints
|
||
* - other error codes from the underlying storage driver
|
||
*/
|
||
esp_err_t nvs_open(const char* name, nvs_open_mode open_mode, nvs_handle *out_handle);
|
||
|
||
/**
|
||
* @brief Open non-volatile storage with a given namespace from specified partition
|
||
*
|
||
* The behaviour is same as nvs_open() API. However this API can operate on a specified NVS
|
||
* partition instead of default NVS partition. Note that the specified partition must be registered
|
||
* with NVS using nvs_flash_init_partition() API.
|
||
*
|
||
* @param[in] part_name Label (name) of the partition of interest for object read/write/erase
|
||
* @param[in] name Namespace name. Maximal length is determined by the
|
||
* underlying implementation, but is guaranteed to be
|
||
* at least 15 characters. Shouldn't be empty.
|
||
* @param[in] open_mode NVS_READWRITE or NVS_READONLY. If NVS_READONLY, will
|
||
* open a handle for reading only. All write requests will
|
||
* be rejected for this handle.
|
||
* @param[out] out_handle If successful (return code is zero), handle will be
|
||
* returned in this argument.
|
||
*
|
||
* @return
|
||
* - ESP_OK if storage handle was opened successfully
|
||
* - ESP_ERR_NVS_NOT_INITIALIZED if the storage driver is not initialized
|
||
* - ESP_ERR_NVS_PART_NOT_FOUND if the partition with specified name is not found
|
||
* - ESP_ERR_NVS_NOT_FOUND id namespace doesn't exist yet and
|
||
* mode is NVS_READONLY
|
||
* - ESP_ERR_NVS_INVALID_NAME if namespace name doesn't satisfy constraints
|
||
* - other error codes from the underlying storage driver
|
||
*/
|
||
esp_err_t nvs_open_from_partition(const char *part_name, const char* name, nvs_open_mode open_mode, nvs_handle *out_handle);
|
||
|
||
/**@{*/
|
||
/**
|
||
* @brief set value for given key
|
||
*
|
||
* This family of functions set value for the key, given its name. Note that
|
||
* actual storage will not be updated until nvs_commit function is called.
|
||
*
|
||
* @param[in] handle Handle obtained from nvs_open function.
|
||
* Handles that were opened read only cannot be used.
|
||
* @param[in] key Key name. Maximal length is determined by the underlying
|
||
* implementation, but is guaranteed to be at least
|
||
* 15 characters. Shouldn't be empty.
|
||
* @param[in] value The value to set.
|
||
* For strings, the maximum length (including null character) is
|
||
* 1984 bytes.
|
||
*
|
||
* @return
|
||
* - ESP_OK if value was set successfully
|
||
* - ESP_ERR_NVS_INVALID_HANDLE if handle has been closed or is NULL
|
||
* - ESP_ERR_NVS_READ_ONLY if storage handle was opened as read only
|
||
* - ESP_ERR_NVS_INVALID_NAME if key name doesn't satisfy constraints
|
||
* - ESP_ERR_NVS_NOT_ENOUGH_SPACE if there is not enough space in the
|
||
* underlying storage to save the value
|
||
* - ESP_ERR_NVS_REMOVE_FAILED if the value wasn't updated because flash
|
||
* write operation has failed. The value was written however, and
|
||
* update will be finished after re-initialization of nvs, provided that
|
||
* flash operation doesn't fail again.
|
||
* - ESP_ERR_NVS_VALUE_TOO_LONG if the string value is too long
|
||
*/
|
||
esp_err_t nvs_set_i8 (nvs_handle handle, const char* key, int8_t value);
|
||
esp_err_t nvs_set_u8 (nvs_handle handle, const char* key, uint8_t value);
|
||
esp_err_t nvs_set_i16 (nvs_handle handle, const char* key, int16_t value);
|
||
esp_err_t nvs_set_u16 (nvs_handle handle, const char* key, uint16_t value);
|
||
esp_err_t nvs_set_i32 (nvs_handle handle, const char* key, int32_t value);
|
||
esp_err_t nvs_set_u32 (nvs_handle handle, const char* key, uint32_t value);
|
||
esp_err_t nvs_set_i64 (nvs_handle handle, const char* key, int64_t value);
|
||
esp_err_t nvs_set_u64 (nvs_handle handle, const char* key, uint64_t value);
|
||
esp_err_t nvs_set_str (nvs_handle handle, const char* key, const char* value);
|
||
/**@}*/
|
||
|
||
/**
|
||
* @brief set variable length binary value for given key
|
||
*
|
||
* This family of functions set value for the key, given its name. Note that
|
||
* actual storage will not be updated until nvs_commit function is called.
|
||
*
|
||
* @param[in] handle Handle obtained from nvs_open function.
|
||
* Handles that were opened read only cannot be used.
|
||
* @param[in] key Key name. Maximal length is 15 characters. Shouldn't be empty.
|
||
* @param[in] value The value to set.
|
||
* @param[in] length length of binary value to set, in bytes; Maximum length is
|
||
* 1984 bytes.
|
||
*
|
||
* @return
|
||
* - ESP_OK if value was set successfully
|
||
* - ESP_ERR_NVS_INVALID_HANDLE if handle has been closed or is NULL
|
||
* - ESP_ERR_NVS_READ_ONLY if storage handle was opened as read only
|
||
* - ESP_ERR_NVS_INVALID_NAME if key name doesn't satisfy constraints
|
||
* - ESP_ERR_NVS_NOT_ENOUGH_SPACE if there is not enough space in the
|
||
* underlying storage to save the value
|
||
* - ESP_ERR_NVS_REMOVE_FAILED if the value wasn't updated because flash
|
||
* write operation has failed. The value was written however, and
|
||
* update will be finished after re-initialization of nvs, provided that
|
||
* flash operation doesn't fail again.
|
||
* - ESP_ERR_NVS_VALUE_TOO_LONG if the value is too long
|
||
*/
|
||
esp_err_t nvs_set_blob(nvs_handle handle, const char* key, const void* value, size_t length);
|
||
|
||
/**@{*/
|
||
/**
|
||
* @brief get value for given key
|
||
*
|
||
* These functions retrieve value for the key, given its name. If key does not
|
||
* exist, or the requested variable type doesn't match the type which was used
|
||
* when setting a value, an error is returned.
|
||
*
|
||
* In case of any error, out_value is not modified.
|
||
*
|
||
* All functions expect out_value to be a pointer to an already allocated variable
|
||
* of the given type.
|
||
*
|
||
* \code{c}
|
||
* // Example of using nvs_get_i32:
|
||
* int32_t max_buffer_size = 4096; // default value
|
||
* esp_err_t err = nvs_get_i32(my_handle, "max_buffer_size", &max_buffer_size);
|
||
* assert(err == ESP_OK || err == ESP_ERR_NVS_NOT_FOUND);
|
||
* // if ESP_ERR_NVS_NOT_FOUND was returned, max_buffer_size will still
|
||
* // have its default value.
|
||
*
|
||
* \endcode
|
||
*
|
||
* @param[in] handle Handle obtained from nvs_open function.
|
||
* @param[in] key Key name. Maximal length is determined by the underlying
|
||
* implementation, but is guaranteed to be at least
|
||
* 15 characters. Shouldn't be empty.
|
||
* @param out_value Pointer to the output value.
|
||
* May be NULL for nvs_get_str and nvs_get_blob, in this
|
||
* case required length will be returned in length argument.
|
||
*
|
||
* @return
|
||
* - ESP_OK if the value was retrieved successfully
|
||
* - ESP_ERR_NVS_NOT_FOUND if the requested key doesn't exist
|
||
* - ESP_ERR_NVS_INVALID_HANDLE if handle has been closed or is NULL
|
||
* - ESP_ERR_NVS_INVALID_NAME if key name doesn't satisfy constraints
|
||
* - ESP_ERR_NVS_INVALID_LENGTH if length is not sufficient to store data
|
||
*/
|
||
esp_err_t nvs_get_i8 (nvs_handle handle, const char* key, int8_t* out_value);
|
||
esp_err_t nvs_get_u8 (nvs_handle handle, const char* key, uint8_t* out_value);
|
||
esp_err_t nvs_get_i16 (nvs_handle handle, const char* key, int16_t* out_value);
|
||
esp_err_t nvs_get_u16 (nvs_handle handle, const char* key, uint16_t* out_value);
|
||
esp_err_t nvs_get_i32 (nvs_handle handle, const char* key, int32_t* out_value);
|
||
esp_err_t nvs_get_u32 (nvs_handle handle, const char* key, uint32_t* out_value);
|
||
esp_err_t nvs_get_i64 (nvs_handle handle, const char* key, int64_t* out_value);
|
||
esp_err_t nvs_get_u64 (nvs_handle handle, const char* key, uint64_t* out_value);
|
||
/**@}*/
|
||
|
||
/**
|
||
* @brief get value for given key
|
||
*
|
||
* These functions retrieve value for the key, given its name. If key does not
|
||
* exist, or the requested variable type doesn't match the type which was used
|
||
* when setting a value, an error is returned.
|
||
*
|
||
* In case of any error, out_value is not modified.
|
||
*
|
||
* All functions expect out_value to be a pointer to an already allocated variable
|
||
* of the given type.
|
||
*
|
||
* nvs_get_str and nvs_get_blob functions support WinAPI-style length queries.
|
||
* To get the size necessary to store the value, call nvs_get_str or nvs_get_blob
|
||
* with zero out_value and non-zero pointer to length. Variable pointed to
|
||
* by length argument will be set to the required length. For nvs_get_str,
|
||
* this length includes the zero terminator. When calling nvs_get_str and
|
||
* nvs_get_blob with non-zero out_value, length has to be non-zero and has to
|
||
* point to the length available in out_value.
|
||
* It is suggested that nvs_get/set_str is used for zero-terminated C strings, and
|
||
* nvs_get/set_blob used for arbitrary data structures.
|
||
*
|
||
* \code{c}
|
||
* // Example (without error checking) of using nvs_get_str to get a string into dynamic array:
|
||
* size_t required_size;
|
||
* nvs_get_str(my_handle, "server_name", NULL, &required_size);
|
||
* char* server_name = malloc(required_size);
|
||
* nvs_get_str(my_handle, "server_name", server_name, &required_size);
|
||
*
|
||
* // Example (without error checking) of using nvs_get_blob to get a binary data
|
||
* into a static array:
|
||
* uint8_t mac_addr[6];
|
||
* size_t size = sizeof(mac_addr);
|
||
* nvs_get_blob(my_handle, "dst_mac_addr", mac_addr, &size);
|
||
* \endcode
|
||
*
|
||
* @param[in] handle Handle obtained from nvs_open function.
|
||
* @param[in] key Key name. Maximal length is determined by the underlying
|
||
* implementation, but is guaranteed to be at least
|
||
* 15 characters. Shouldn't be empty.
|
||
* @param out_value Pointer to the output value.
|
||
* May be NULL for nvs_get_str and nvs_get_blob, in this
|
||
* case required length will be returned in length argument.
|
||
* @param[inout] length A non-zero pointer to the variable holding the length of out_value.
|
||
* In case out_value a zero, will be set to the length
|
||
* required to hold the value. In case out_value is not
|
||
* zero, will be set to the actual length of the value
|
||
* written. For nvs_get_str this includes zero terminator.
|
||
*
|
||
* @return
|
||
* - ESP_OK if the value was retrieved successfully
|
||
* - ESP_ERR_NVS_NOT_FOUND if the requested key doesn't exist
|
||
* - ESP_ERR_NVS_INVALID_HANDLE if handle has been closed or is NULL
|
||
* - ESP_ERR_NVS_INVALID_NAME if key name doesn't satisfy constraints
|
||
* - ESP_ERR_NVS_INVALID_LENGTH if length is not sufficient to store data
|
||
*/
|
||
/**@{*/
|
||
esp_err_t nvs_get_str (nvs_handle handle, const char* key, char* out_value, size_t* length);
|
||
esp_err_t nvs_get_blob(nvs_handle handle, const char* key, void* out_value, size_t* length);
|
||
/**@}*/
|
||
|
||
/**
|
||
* @brief Erase key-value pair with given key name.
|
||
*
|
||
* Note that actual storage may not be updated until nvs_commit function is called.
|
||
*
|
||
* @param[in] handle Storage handle obtained with nvs_open.
|
||
* Handles that were opened read only cannot be used.
|
||
*
|
||
* @param[in] key Key name. Maximal length is determined by the underlying
|
||
* implementation, but is guaranteed to be at least
|
||
* 15 characters. Shouldn't be empty.
|
||
*
|
||
* @return
|
||
* - ESP_OK if erase operation was successful
|
||
* - ESP_ERR_NVS_INVALID_HANDLE if handle has been closed or is NULL
|
||
* - ESP_ERR_NVS_READ_ONLY if handle was opened as read only
|
||
* - ESP_ERR_NVS_NOT_FOUND if the requested key doesn't exist
|
||
* - other error codes from the underlying storage driver
|
||
*/
|
||
esp_err_t nvs_erase_key(nvs_handle handle, const char* key);
|
||
|
||
/**
|
||
* @brief Erase all key-value pairs in a namespace
|
||
*
|
||
* Note that actual storage may not be updated until nvs_commit function is called.
|
||
*
|
||
* @param[in] handle Storage handle obtained with nvs_open.
|
||
* Handles that were opened read only cannot be used.
|
||
*
|
||
* @return
|
||
* - ESP_OK if erase operation was successful
|
||
* - ESP_ERR_NVS_INVALID_HANDLE if handle has been closed or is NULL
|
||
* - ESP_ERR_NVS_READ_ONLY if handle was opened as read only
|
||
* - other error codes from the underlying storage driver
|
||
*/
|
||
esp_err_t nvs_erase_all(nvs_handle handle);
|
||
|
||
/**
|
||
* @brief Write any pending changes to non-volatile storage
|
||
*
|
||
* After setting any values, nvs_commit() must be called to ensure changes are written
|
||
* to non-volatile storage. Individual implementations may write to storage at other times,
|
||
* but this is not guaranteed.
|
||
*
|
||
* @param[in] handle Storage handle obtained with nvs_open.
|
||
* Handles that were opened read only cannot be used.
|
||
*
|
||
* @return
|
||
* - ESP_OK if the changes have been written successfully
|
||
* - ESP_ERR_NVS_INVALID_HANDLE if handle has been closed or is NULL
|
||
* - other error codes from the underlying storage driver
|
||
*/
|
||
esp_err_t nvs_commit(nvs_handle handle);
|
||
|
||
/**
|
||
* @brief Close the storage handle and free any allocated resources
|
||
*
|
||
* This function should be called for each handle opened with nvs_open once
|
||
* the handle is not in use any more. Closing the handle may not automatically
|
||
* write the changes to nonvolatile storage. This has to be done explicitly using
|
||
* nvs_commit function.
|
||
* Once this function is called on a handle, the handle should no longer be used.
|
||
*
|
||
* @param[in] handle Storage handle to close
|
||
*/
|
||
void nvs_close(nvs_handle handle);
|
||
|
||
/**
|
||
* @note Info about storage space NVS.
|
||
*/
|
||
typedef struct {
|
||
size_t used_entries; /**< Amount of used entries. */
|
||
size_t free_entries; /**< Amount of free entries. */
|
||
size_t total_entries; /**< Amount all available entries. */
|
||
size_t namespace_count; /**< Amount name space. */
|
||
} nvs_stats_t;
|
||
|
||
/**
|
||
* @brief Fill structure nvs_stats_t. It provides info about used memory the partition.
|
||
*
|
||
* This function calculates to runtime the number of used entries, free entries, total entries,
|
||
* and amount namespace in partition.
|
||
*
|
||
* \code{c}
|
||
* // Example of nvs_get_stats() to get the number of used entries and free entries:
|
||
* nvs_stats_t nvs_stats;
|
||
* nvs_get_stats(NULL, &nvs_stats);
|
||
* printf("Count: UsedEntries = (%d), FreeEntries = (%d), AllEntries = (%d)\n",
|
||
nvs_stats.used_entries, nvs_stats.free_entries, nvs_stats.total_entries);
|
||
* \endcode
|
||
*
|
||
* @param[in] part_name Partition name NVS in the partition table.
|
||
* If pass a NULL than will use NVS_DEFAULT_PART_NAME ("nvs").
|
||
*
|
||
* @param[out] nvs_stats Returns filled structure nvs_states_t.
|
||
* It provides info about used memory the partition.
|
||
*
|
||
*
|
||
* @return
|
||
* - ESP_OK if the changes have been written successfully.
|
||
* Return param nvs_stats will be filled.
|
||
* - ESP_ERR_NVS_PART_NOT_FOUND if the partition with label "name" is not found.
|
||
* Return param nvs_stats will be filled 0.
|
||
* - ESP_ERR_NVS_NOT_INITIALIZED if the storage driver is not initialized.
|
||
* Return param nvs_stats will be filled 0.
|
||
* - ESP_ERR_INVALID_ARG if nvs_stats equal to NULL.
|
||
* - ESP_ERR_INVALID_STATE if there is page with the status of INVALID.
|
||
* Return param nvs_stats will be filled not with correct values because
|
||
* not all pages will be counted. Counting will be interrupted at the first INVALID page.
|
||
*/
|
||
esp_err_t nvs_get_stats(const char* part_name, nvs_stats_t* nvs_stats);
|
||
|
||
/**
|
||
* @brief Calculate all entries in a namespace.
|
||
*
|
||
* Note that to find out the total number of records occupied by the namespace,
|
||
* add one to the returned value used_entries (if err is equal to ESP_OK).
|
||
* Because the name space entry takes one entry.
|
||
*
|
||
* \code{c}
|
||
* // Example of nvs_get_used_entry_count() to get amount of all key-value pairs in one namespace:
|
||
* nvs_handle handle;
|
||
* nvs_open("namespace1", NVS_READWRITE, &handle);
|
||
* ...
|
||
* size_t used_entries;
|
||
* size_t total_entries_namespace;
|
||
* if(nvs_get_used_entry_count(handle, &used_entries) == ESP_OK){
|
||
* // the total number of records occupied by the namespace
|
||
* total_entries_namespace = used_entries + 1;
|
||
* }
|
||
* \endcode
|
||
*
|
||
* @param[in] handle Handle obtained from nvs_open function.
|
||
*
|
||
* @param[out] used_entries Returns amount of used entries from a namespace.
|
||
*
|
||
*
|
||
* @return
|
||
* - ESP_OK if the changes have been written successfully.
|
||
* Return param used_entries will be filled valid value.
|
||
* - ESP_ERR_NVS_NOT_INITIALIZED if the storage driver is not initialized.
|
||
* Return param used_entries will be filled 0.
|
||
* - ESP_ERR_NVS_INVALID_HANDLE if handle has been closed or is NULL.
|
||
* Return param used_entries will be filled 0.
|
||
* - ESP_ERR_INVALID_ARG if nvs_stats equal to NULL.
|
||
* - Other error codes from the underlying storage driver.
|
||
* Return param used_entries will be filled 0.
|
||
*/
|
||
esp_err_t nvs_get_used_entry_count(nvs_handle handle, size_t* used_entries);
|
||
|
||
#ifdef __cplusplus
|
||
} // extern "C"
|
||
#endif
|
||
|
||
#endif //ESP_NVS_H
|
||
|