OVMS3-idf/components/nvs_flash/include/nvs.h
Ivan Grokhotkov 7998b6ca2e components/nvs: handle more cases where sudden power off may happen
This commit fixes several issues with state handling in nvs::Page. It also adds extra consistency checks in nvs::PageManger initialization.
These changes were verified with a new long-running test ("test recovery from sudden poweroff"). This test works by repeatedly performing same pseudorandom sequence of calls to nvs_ APIs. Each time it repeats the sequence, it introduces a failure into one of flash operations (write or erase). So if one iteration of this test needs, say, 25000 flash operations, then this test will run 25000 iterations, each time introducing the failure point at different location.
2016-08-23 12:08:00 +08:00

218 lines
11 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
#define ESP_ERR_NVS_NOT_INITIALIZED (ESP_ERR_NVS_BASE + 0x01)
#define ESP_ERR_NVS_NOT_FOUND (ESP_ERR_NVS_BASE + 0x02)
#define ESP_ERR_NVS_TYPE_MISMATCH (ESP_ERR_NVS_BASE + 0x03)
#define ESP_ERR_NVS_READ_ONLY (ESP_ERR_NVS_BASE + 0x04)
#define ESP_ERR_NVS_NOT_ENOUGH_SPACE (ESP_ERR_NVS_BASE + 0x05)
#define ESP_ERR_NVS_INVALID_NAME (ESP_ERR_NVS_BASE + 0x06)
#define ESP_ERR_NVS_INVALID_HANDLE (ESP_ERR_NVS_BASE + 0x07)
#define ESP_ERR_NVS_REMOVE_FAILED (ESP_ERR_NVS_BASE + 0x08)
#define ESP_ERR_NVS_KEY_TOO_LONG (ESP_ERR_NVS_BASE + 0x09)
#define ESP_ERR_NVS_PAGE_FULL (ESP_ERR_NVS_BASE + 0x0a)
#define ESP_ERR_NVS_INVALID_STATE (ESP_ERR_NVS_BASE + 0x0b)
#define ESP_ERR_NVS_INVALID_LENGTH (ESP_ERR_NVS_BASE + 0x0c)
typedef enum {
NVS_READONLY,
NVS_READWRITE
} nvs_open_mode;
/**
* @brief Open non-volatile storage with a given namespace
*
* 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.
*
* @param[in] name Namespace name. Maximal length is determined by the
* underlying implementation, but is guaranteed to be
* at least 16 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_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 nvs_set_X - 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. If the handle was
* opened with read_only set to true, nvs_set_X functions will
* fail with ESP_ERR_NVS_READONLY.
* @param[in] key Key name. Maximal length is determined by the underlying
* implementation, but is guaranteed to be at least
* 16 characters. Shouldn't be empty.
* @param[in] value The value to set.
* @param[in] length For nvs_set_blob: length of binary value to set, in 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_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);
esp_err_t nvs_set_blob(nvs_handle handle, const char* key, const void* value, size_t length);
/**
* @brief nvs_get_X - 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.
* Additionally, nvs_get_str and nvs_get_blob 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.
*
* 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.
*
* 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);
*
* @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
* 16 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 For nvs_get_str and nvs_get_blob, 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_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);
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 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. If handle has to be
* opened as not read only for this call to succeed.
*
* @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);
#ifdef __cplusplus
} // extern "C"
#endif
#endif //ESP_NVS_H