esp-idf/components/nvs_flash/src/compressed_enum_table.hpp
Matus Fabo 58cca07104 add: Kconfig assert or errorcode option
add: private include header
add: macro encapsulation for assertion or error check
add: ESP_FAIL return code documentation in public headers
change: replaced all assertions by NVS_ASSERT_OR_RETURN macro
change: few internal function return values from void to esp_err_t
change: ESP_ERR_NVS_VALUE_TOO_LONG macro comment
2022-05-28 20:29:05 +02:00

76 lines
1.8 KiB
C++

/*
* SPDX-FileCopyrightText: 2015-2022 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef compressed_enum_table_h
#define compressed_enum_table_h
#include <cstdint>
#include <cassert>
#include <type_traits>
#include "nvs_internal.h"
#include "esp_err.h"
template<typename Tenum, size_t Nbits, size_t Nitems>
class CompressedEnumTable
{
public:
uint32_t* data()
{
return mData;
}
const uint32_t* data() const
{
return mData;
}
esp_err_t get(size_t index, Tenum *retval) const
{
NVS_ASSERT_OR_RETURN(index < Nitems, ESP_FAIL);
size_t wordIndex = index / ITEMS_PER_WORD;
size_t offset = (index % ITEMS_PER_WORD) * Nbits;
*retval = static_cast<Tenum>((mData[wordIndex] >> offset) & VALUE_MASK);
return ESP_OK;
}
esp_err_t set(size_t index, Tenum val)
{
NVS_ASSERT_OR_RETURN(index < Nitems, ESP_FAIL);
size_t wordIndex = index / ITEMS_PER_WORD;
size_t offset = (index % ITEMS_PER_WORD) * Nbits;
uint32_t v = static_cast<uint32_t>(val) << offset;
mData[wordIndex] = (mData[wordIndex] & ~(VALUE_MASK << offset)) | v;
return ESP_OK;
}
static constexpr size_t getWordIndex(size_t index)
{
return index / ITEMS_PER_WORD;
}
static constexpr size_t byteSize()
{
return WORD_COUNT * 4;
}
static constexpr size_t count()
{
return Nitems;
}
protected:
static_assert(32 % Nbits == 0, "Nbits must divide 32");
static const size_t ITEMS_PER_WORD = 32 / Nbits;
static const size_t WORD_COUNT = ( Nbits * Nitems + 31 ) / 32;
static const uint32_t VALUE_MASK = (1 << Nbits) - 1;
uint32_t mData[WORD_COUNT];
};
#endif /* compressed_enum_table_h */