blob: a87140a7be279b0d04a3d99df8a9e15b51d24dce [file] [log] [blame]
/*
*
* Copyright (c) 2021 Project CHIP Authors
*
* 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.
*/
#pragma once
#include <cstddef>
#include <cstdint>
namespace chip {
/**
* Memory allocator that uses a fixed-size buffer.
*
* This class allocates subsequent memory regions out of a fixed-size buffer.
* Deallocation of specific regions is unsupported and it is assumed that the entire
* buffer will be released at once.
*/
class FixedBufferAllocator
{
public:
FixedBufferAllocator() = default;
FixedBufferAllocator(uint8_t * buffer, size_t capacity) { Init(buffer, capacity); }
template <size_t N>
explicit FixedBufferAllocator(uint8_t (&buffer)[N])
{
Init(buffer);
}
void Init(uint8_t * buffer, size_t capacity)
{
mBegin = buffer;
mEnd = buffer + capacity;
mAnyAllocFailed = false;
}
template <size_t N>
void Init(uint8_t (&buffer)[N])
{
Init(buffer, N);
}
/**
* Allocate a specified number of bytes.
*
* @param count Number of bytes to allocate.
* @return Pointer to the allocated memory region or nullptr on failure.
*/
uint8_t * Alloc(size_t count);
/**
* Allocate memory for the specified data and copy the data into the allocated region.
*
* @param data Pointer to the data to be copied into the allocated memory region.
* @param dataLen Size of the data to be copied into the allocated memory region.
* @return Pointer to the allocated memory region or nullptr on failure.
*/
uint8_t * Clone(const void * data, size_t dataLen);
/**
* Allocate memory for the specified string and copy the string, including
* the null-character, into the allocated region.
*
* @param str Pointer to the string to be copied into the allocated memory region.
* @return Pointer to the allocated memory region or nullptr on failure.
*/
char * Clone(const char * str);
/**
* Returns whether any allocation has failed so far.
*/
bool AnyAllocFailed() const { return mAnyAllocFailed; }
private:
FixedBufferAllocator(const FixedBufferAllocator &) = delete;
void operator=(const FixedBufferAllocator &) = delete;
uint8_t * mBegin = nullptr;
uint8_t * mEnd = nullptr;
bool mAnyAllocFailed = false;
};
} // namespace chip