libcryfs/random/RandomDataBuffer.h

51 lines
1.3 KiB
C++

#pragma once
#ifndef MESSMER_CPPUTILS_RANDOM_RANDOMDATABUFFER_H
#define MESSMER_CPPUTILS_RANDOM_RANDOMDATABUFFER_H
#include "../data/Data.h"
#include "../assert/assert.h"
namespace cpputils {
//TODO Test
class RandomDataBuffer {
public:
RandomDataBuffer();
size_t size() const;
void get(void *target, size_t bytes);
void add(Data data);
private:
size_t _usedUntil;
Data _data;
DISALLOW_COPY_AND_ASSIGN(RandomDataBuffer);
};
inline RandomDataBuffer::RandomDataBuffer() : _data(0) {
}
inline size_t RandomDataBuffer::size() const {
return _data.size() - _usedUntil;
}
inline void RandomDataBuffer::get(void *target, size_t numBytes) {
ASSERT(size() >= numBytes, "Too many bytes requested. Buffer is smaller.");
std::memcpy(target, _data.dataOffset(_usedUntil), numBytes);
_usedUntil += numBytes;
}
inline void RandomDataBuffer::add(Data data) {
// Concatenate old and new random data
Data newdata(_data.size() + data.size());
std::memcpy(newdata.data(), _data.data(), _data.size());
std::memcpy(newdata.dataOffset(_data.size()), data.data(), data.size());
_data = std::move(newdata);
}
}
#endif