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Merge branch 'doc/nvs_max_num_namespaces_4.4' into 'release/v4.4'

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doc (nvs): added note about maximum possible namespaces (backport 4.4)

See merge request espressif/esp-idf!19980
This commit is contained in:
Zim Kalinowski 2022-09-13 17:33:19 +08:00
commit 5224045d17
3 changed files with 6 additions and 2 deletions
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4
components/nvs_flash/include/nvs.h
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@ -132,6 +132,8 @@ typedef struct nvs_opaque_iterator_t *nvs_iterator_t;
* mode is NVS_READONLY
* - ESP_ERR_NVS_INVALID_NAME if namespace name doesn't satisfy constraints
* - ESP_ERR_NO_MEM in case memory could not be allocated for the internal structures
* - ESP_ERR_NVS_NOT_ENOUGH_SPACE if there is no space for a new entry or there are too many different
* namespaces (maximum allowed different namespaces: 254)
* - other error codes from the underlying storage driver
*/
esp_err_t nvs_open(const char* name, nvs_open_mode_t open_mode, nvs_handle_t *out_handle);
@ -161,6 +163,8 @@ esp_err_t nvs_open(const char* name, nvs_open_mode_t open_mode, nvs_handle_t *ou
* mode is NVS_READONLY
* - ESP_ERR_NVS_INVALID_NAME if namespace name doesn't satisfy constraints
* - ESP_ERR_NO_MEM in case memory could not be allocated for the internal structures
* - ESP_ERR_NVS_NOT_ENOUGH_SPACE if there is no space for a new entry or there are too many different
* namespaces (maximum allowed different namespaces: 254)
* - 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_t open_mode, nvs_handle_t *out_handle);

2
docs/en/api-reference/storage/nvs_flash.rst
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@ -46,7 +46,7 @@ Data type check is also performed when reading a value. An error is returned if
Namespaces
^^^^^^^^^^
To mitigate potential conflicts in key names between different components, NVS assigns each key-value pair to one of namespaces. Namespace names follow the same rules as key names, i.e., the maximum length is 15 characters. Namespace name is specified in the :cpp:func:`nvs_open` or :cpp:type:`nvs_open_from_partition` call. This call returns an opaque handle, which is used in subsequent calls to the ``nvs_get_*``, ``nvs_set_*``, and :cpp:func:`nvs_commit` functions. This way, a handle is associated with a namespace, and key names will not collide with same names in other namespaces. Please note that the namespaces with the same name in different NVS partitions are considered as separate namespaces.
To mitigate potential conflicts in key names between different components, NVS assigns each key-value pair to one of namespaces. Namespace names follow the same rules as key names, i.e., the maximum length is 15 characters. Furthermore, there can be no more than 254 different namespaces in one NVS partition. Namespace name is specified in the :cpp:func:`nvs_open` or :cpp:type:`nvs_open_from_partition` call. This call returns an opaque handle, which is used in subsequent calls to the ``nvs_get_*``, ``nvs_set_*``, and :cpp:func:`nvs_commit` functions. This way, a handle is associated with a namespace, and key names will not collide with same names in other namespaces. Please note that the namespaces with the same name in different NVS partitions are considered as separate namespaces.
NVS iterators
^^^^^^^^^^^^^

2
docs/zh_CN/api-reference/storage/nvs_flash.rst
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@ -46,7 +46,7 @@ NVS 的操作对象为键值对，其中键是 ASCII 字符串，当前支持的
命名空间
^^^^^^^^^^
为了减少不同组件之间键名的潜在冲突，NVS 将每个键值对分配给一个命名空间。命名空间的命名规则遵循键名的命名规则，例如，最多可占 15 个字符。命名空间的名称在调用 :cpp:func:`nvs_open` 或 :cpp:type:`nvs_open_from_partition` 中指定，调用后将返回一个不透明句柄，用于后续调用 ``nvs_get_*``、``nvs_set_*`` 和 ``nvs_commit`` 函数。这样，一个句柄关联一个命名空间，键名便不会与其他命名空间中相同键名冲突。请注意，不同 NVS 分区中具有相同名称的命名空间将被视为不同的命名空间。
为了减少不同组件之间键名的潜在冲突，NVS 将每个键值对分配给一个命名空间。命名空间的命名规则遵循键名的命名规则，例如，最多可占 15 个字符。此外，单个 NVS 分区最多只能容纳 254 个不同的命名空间。命名空间的名称在调用 :cpp:func:`nvs_open` 或 :cpp:type:`nvs_open_from_partition` 中指定，调用后将返回一个不透明句柄，用于后续调用 ``nvs_get_*``、``nvs_set_*`` 和 ``nvs_commit`` 函数。这样，一个句柄关联一个命名空间，键名便不会与其他命名空间中相同键名冲突。请注意，不同 NVS 分区中具有相同名称的命名空间将被视为不同的命名空间。
NVS 迭代器
^^^^^^^^^^^^^