Mbed OS Reference | KVStore.h Source File

 /*
  * Copyright (c) 2018 ARM Limited. All rights reserved.
  * SPDX-License-Identifier: Apache-2.0
  * 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 MBED_KVSTORE_H
 #define MBED_KVSTORE_H
 
 #include <stdint.h>
 #include <stdio.h>
 #include <string.h>
 
 namespace mbed {
 
 /** KVStore class
  *
  *  Interface class for Key Value Storage
  */
 class KVStore {
 public:
     enum create_flags {
         WRITE_ONCE_FLAG                     = (1 << 0),
         REQUIRE_CONFIDENTIALITY_FLAG        = (1 << 1),
         RESERVED_FLAG                       = (1 << 2),
         REQUIRE_REPLAY_PROTECTION_FLAG      = (1 << 3),
     };
 
     static const uint32_t MAX_KEY_SIZE = 128;
 
     typedef struct _opaque_set_handle *set_handle_t;
 
     typedef struct _opaque_key_iterator *iterator_t;
 
     /**
      * Holds key information
      */
     typedef struct info {
         /**
          * The key size
          */
         size_t size;
         /*
          * The Key flags, possible flags combination:
          * WRITE_ONCE_FLAG,
          * REQUIRE_CONFIDENTIALITY_FLAG,
          * REQUIRE_REPLAY_PROTECTION_FLAG
          */
         uint32_t flags;
     } info_t;
 
     virtual ~KVStore() {};
 
     /**
      * @brief Initialize KVStore
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int init() = 0;
 
     /**
      * @brief Deinitialize KVStore
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int deinit() = 0;
 
 
     /**
      * @brief Reset KVStore contents (clear all keys)
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int reset() = 0;
 
     /**
      * @brief Set one KVStore item, given key and value.
      *
      * @param[in]  key                  Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
      * @param[in]  buffer               Value data buffer.
      * @param[in]  size                 Value data size.
      * @param[in]  create_flags         Flag mask.
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int set(const char *key, const void *buffer, size_t size, uint32_t create_flags) = 0;
 
     /**
      * @brief Get one KVStore item, given key.
      *
      * @param[in]  key                  Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
      * @param[in]  buffer               Value data buffer.
      * @param[in]  buffer_size          Value data buffer size.
      * @param[out] actual_size          Actual read size (NULL to pass nothing).
      * @param[in]  offset               Offset to read from in data.
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int get(const char *key, void *buffer, size_t buffer_size, size_t *actual_size = NULL, size_t offset = 0) = 0;
 
     /**
      * @brief Get information of a given key.
      *
      * @param[in]  key                  Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
      * @param[out] info                 Returned information structure (NULL to pass nothing).
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int get_info(const char *key, info_t *info = NULL) = 0;
 
     /**
      * @brief Remove a KVStore item, given key.
      *
      * @param[in]  key                  Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int remove(const char *key) = 0;
 
 
     /**
      * @brief Start an incremental KVStore set sequence.
      *
      * @param[out] handle               Returned incremental set handle.
      * @param[in]  key                  Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
      * @param[in]  final_data_size      Final value data size.
      * @param[in]  create_flags         Flag mask.
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int set_start(set_handle_t *handle, const char *key, size_t final_data_size, uint32_t create_flags) = 0;
 
     /**
      * @brief Add data to incremental KVStore set sequence.
      *
      * @param[in]  handle               Incremental set handle.
      * @param[in]  value_data           Value data to add.
      * @param[in]  data_size            Value data size.
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int set_add_data(set_handle_t handle, const void *value_data, size_t data_size) = 0;
 
     /**
      * @brief Finalize an incremental KVStore set sequence.
      *
      * @param[in]  handle               Incremental set handle.
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int set_finalize(set_handle_t handle) = 0;
 
     /**
      * @brief Start an iteration over KVStore keys.
      *
      * @param[out] it                   Returned iterator handle.
      * @param[in]  prefix               Key prefix (null for all keys).
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int iterator_open(iterator_t *it, const char *prefix = NULL) = 0;
 
     /**
      * @brief Get next key in iteration.
      *
      * @param[in]  it                   Iterator handle.
      * @param[in]  key                  Buffer for returned key.
      * @param[in]  key_size             Key buffer size.
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int iterator_next(iterator_t it, char *key, size_t key_size) = 0;
 
     /**
      * @brief Close iteration.
      *
      * @param[in]  it                   Iterator handle.
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     virtual int iterator_close(iterator_t it) = 0;
 
     /** Convenience function for checking key validity.
      *  Key must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
      *
      * @param[in]  key                  Key buffer.
      *
      * @returns MBED_SUCCESS on success or an error code on failure
      */
     bool is_valid_key(const char *key) const
     {
         if (!key || !strlen(key) || (strlen(key) > MAX_KEY_SIZE)) {
             return false;
         }
 
         if (strpbrk(key, " */?:;\"|<>\\")) {
             return false;
         }
         return true;
     }
 
 };
 /** @}*/
 
 } // namespace mbed
 
 #endif
Important Information for this Arm website
